Saturday, April 20, 2013
Dating game
Can Sex Education Delay Early Sexual Debut?
Sumru Erkut et al.
Journal of Early Adolescence, May 2013, Pages 482-497
Abstract:
In this study, we examine whether a nine-lesson sex education intervention, "Get Real: Comprehensive Sex Education That Works," implemented in sixth grade, can reduce the number of adolescents who might otherwise become "early starters" of sexual activity (defined as heterosexual intercourse) by seventh grade. Participants were 548 boys and 675 girls who completed surveys in both sixth grade (baseline) and seventh grade (follow-up). The sample was 35% Latino, 32% Black, 24% White, 3% Asian, and 6% biracial. Students randomly assigned to the control condition were 30% more likely to initiate sex by follow-up when controlling for having had sex by sixth grade, demographic variables, and a tendency to give socially desirable responses. This finding is noteworthy because previous research has identified early starters to be prone to poor outcomes in sexual health, family formation, economic security, and incarceration and few middle school interventions have shown an effect on behavioral outcomes.
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Suchi Pradyumn Joshi, Jochen Peter & Patti Valkenburg
Journal of Sex Research, forthcoming
Abstract:
This quantitative content analysis investigated the hookup culture in U.S. and Dutch teen girl magazines. Using Hofstede's cultural dimension of masculinity/femininity, the hookup culture (i.e., the relational context of sex, emotional context of sex, specific sexual activities, and contraceptives) was examined in 2,496 stories from all 2006 through 2008 issues of the three most popular U.S. (i.e., Seventeen, CosmoGirl! U.S. edition, and Teen) and Dutch teen girl magazines (i.e., Fancy, CosmoGirl! Netherlands edition, and Girlz!). Regarding the relational context of sex, stories about casual sex occurred more often in U.S. magazines, and Dutch magazines focused more on committed sex. Dutch magazines also emphasized sex within the emotional context of love more often than did U.S. magazines. In terms of sexual activities, coital sex was mentioned more often in U.S. coverage, while petting was mentioned more frequently in Dutch coverage. Condoms were covered more positively in U.S. magazines than in Dutch magazines. Overall, the hookup culture seems to be more visible in U.S. magazines for the occurrence of casual sex and lack of love stories, whereas it does not emerge in Dutch magazines due to the presence of committed sex and love-related articles.
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Tim Wadsworth
Social Indicators Research, forthcoming
Abstract:
A growing literature suggests that income, marriage, friendship, sex, and a variety of other factors influence self-reported happiness. Why these characteristics matter has been less examined. Scholars have recently demonstrated that part of the effect of income is relative. More income makes people happier, in part, because it sets them above their peers. Until now, the role of relative comparison in the study of happiness has been limited to income. The current work extends this focus to another activity - sex. Using GSS data, I examine how respondents' frequency of sex, as well as the average sexual frequency of their cohort, influences their happiness. The findings suggest that happiness is positively correlated with their own sexual frequency, but inversely correlated with the sexual frequency of others.
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Are Narcissists Sexy? Zeroing in on the Effect of Narcissism on Short-Term Mate Appeal
Michael Dufner et al.
Personality and Social Psychology Bulletin, forthcoming
Abstract:
This research was aimed to provide a comprehensive test of the classic notion that narcissistic individuals are appealing as short-term romantic or sexual partners. In three studies, we tested the hypotheses that narcissism exerts a positive effect on an individual's mate appeal and that this effect is mediated by high physical attractiveness and high social boldness. We implemented a multimethod approach and used ratings of opposite sex persons (Study 1), ratings of friends (Study 2), and records of courtship outcomes in naturalistic interactions (Study 3) as indicators of mate appeal. In all cases, narcissism had a positive effect on mate appeal, which was mainly due to the agentic self-enhancement aspects of narcissism (rather than narcissists' lacking communion). As predicted, physical attractiveness and social boldness mediated the positive effect of narcissism on mate appeal. Findings further indicated that narcissism was more strongly linked to mate appeal than to friend appeal.
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Marie Heffernan & Chris Fraley
Journal of Research in Personality, August 2013, Pages 364-368
Abstract:
The purpose of this research was to examine whether early caregiving experiences are associated with adult mate preferences. Participants completed an online survey in which they rated the attractiveness of target faces. Participants born to older parents were more attracted to older faces compared with participants born to younger parents. The results are consistent with the idea that early experiences may play a role in shaping later mate preferences.
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Compensated for Life: Sex Work and Disease Risk
Raj Arunachalam & Manisha Shah
Journal of Human Resources, Spring 2013, Pages 345-369
Abstract:
Sex workers draw a premium for engaging in unprotected sex. We theoretically motivate a test of whether this premium represents a compensating differential for disease, thereby mitigating sex workers' propensity to use condoms. Using transaction-level data and biological STI markers from sex workers in Ecuador, we exploit within-worker variation across local disease environments. We find that locations with low disease prevalence exhibit a very low, insignificant premium for unprotected sex. A one percentage point increase in the local disease rate increases the premium for noncondom sex by 33 percent. Market forces may curb the self-limiting nature of STI epidemics.
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Compliments and Receptivity to a Courtship Request: A Field Experiment
Nicolas Guéguen, Jacques Fischer-Lokou & Lubomir Lamy
Psychological Reports, February 2013, Pages 239-242
Abstract:
160 young women were solicited in the street to have a drink with a young male confederate. In the ingratiation condition, the solicitor complimented the woman regarding her physical appearance before making the request, while in the no-compliment condition, the confederate asked his request directly. Results showed that complimenting was associated with greater compliance to the request.
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Networks as Covers: Evidence from an On-Line Social Network
Mikolaj Jan Piskorski
Harvard Working Paper, March 2013
Abstract:
This paper proposes that networks give actors a cover by giving them the excuse of sociability to engage in normatively prohibited market behaviors. I apply this hypothesis to actors in long-term exclusive relationships who are surreptitiously seeking new relationships without jeopardizing their current ones. I hypothesize that these actors will be drawn to social environments where others socialize with their friends, and that they will establish numerous relationships in these environments to cover up their real intent. I find significant support for these predictions using data from a large on-line social network.
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Dads or cads? Women's strategic decisions in the mating game
Susan Aitken, Minna Lyons & Peter Jonason
Personality and Individual Differences, forthcoming
Abstract:
We report the findings of two studies (N = 142; N = 28) investigating women's preference for men in short- and long-term mating scenarios and perceptions of honesty of dating adverts written by men high or low in Machiavellianism. Overall, men low on Machiavellianism (viz., dads), were preferred as long-term mates; and men high on Machiavellianism (viz., cads) as short-term mates. Fertile women preferred cads for a short-term relationship and dads as a long-term partner. Higher ratings were given to all adverts when females were fertile, suggesting generally higher levels of desire for a partner when the possibility of conception is highest. In contrast to previous work suggesting traits like Machiavellianism may facilitate a deceptive or exploitative mating strategy in men, the present results suggest (1) women are attuned to differences in men's personality as a function of fertility and (2) affirms that women prefer cads for short-term mating and dads for long-term mating.
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Penis size interacts with body shape and height to influence male attractiveness
Brian Mautz et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
Compelling evidence from many animal taxa indicates that male genitalia are often under postcopulatory sexual selection for characteristics that increase a male's relative fertilization success. There could, however, also be direct precopulatory female mate choice based on male genital traits. Before clothing, the nonretractable human penis would have been conspicuous to potential mates. This observation has generated suggestions that human penis size partly evolved because of female choice. Here we show, based upon female assessment of digitally projected life-size, computer-generated images, that penis size interacts with body shape and height to determine male sexual attractiveness. Positive linear selection was detected for penis size, but the marginal increase in attractiveness eventually declined with greater penis size (i.e., quadratic selection). Penis size had a stronger effect on attractiveness in taller men than in shorter men. There was a similar increase in the positive effect of penis size on attractiveness with a more masculine body shape (i.e., greater shoulder-to-hip ratio). Surprisingly, larger penis size and greater height had almost equivalent positive effects on male attractiveness. Our results support the hypothesis that female mate choice could have driven the evolution of larger penises in humans. More broadly, our results show that precopulatory sexual selection can play a role in the evolution of genital traits.
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Terri Fisher
Sex Roles, April 2013, Pages 401-414
Abstract:
Previous studies have indicated that the research context has an influence on whether gender differences are found in sexual behavior, likely due to adherence to different gender norms for men and women. The present study utilized bogus pipeline methodology to help determine if the purported use of a lie detector would influence gender differences in reports of other types of behaviors considered more suitable for one gender or the other. Participants consisted of General Psychology students attending a regional campus of a major Midwestern university in the United States. Approximately half of 293 participants completed a questionnaire while connected to non-functioning lie detection equipment and the other half completed the questionnaire after the equipment had been disconnected. There were interactions between gender of participant and testing condition for sexual behavior but not for other types of common behaviors considered more appropriate for one gender or the other. This suggests that there is something specific to sexual behavior with regard to a differential willingness between men and women to report behavior unless there is pressure to be honest. Hypergender ideology was related to reports of sexual behavior (but not nonsexual behavior) only for men in the bogus pipeline condition, lending further support to the idea that gender role expectations influence reports of sexual behavior more than reports of other types of behavior.
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Barnaby Dixson & Robert Brooks
Evolution and Human Behavior, May 2013, Pages 236-241
Abstract:
Facial hair strongly influences people's judgments of men's socio-sexual attributes. However, the nature of these judgments is often contradictory. The levels of intermediate facial hair growth presented to raters and the stage of female raters' menstrual cycles might have influenced past findings. We quantified men's and women's judgments of attractiveness, health, masculinity and parenting abilities for photographs of men who were clean-shaven, lightly or heavily stubbled and fully bearded. We also tested the effect of the menstrual cycle and hormonal contraceptive use on women's ratings. Women judged faces with heavy stubble as most attractive and heavy beards, light stubble and clean-shaven faces as similarly less attractive. In contrast, men rated full beards and heavy stubble as most attractive, followed closely by clean-shaven and light stubble as least attractive. Men and women rated full beards highest for parenting ability and healthiness. Masculinity ratings increased linearly as facial hair increased, and this effect was more pronounced in women in the fertile phase of the menstrual cycle, although attractiveness ratings did not differ according to fertility. Our findings confirm that beardedness affects judgments of male socio-sexual attributes and suggest that an intermediate level of beardedness is most attractive while full-bearded men may be perceived as better fathers who could protect and invest in offspring.
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Hooking Up and Penetrative Hookups: Correlates that Differentiate College Men
Spencer Olmstead, Kay Pasley & Frank Fincham
Archives of Sexual Behavior, May 2013, Pages 573-583
Abstract:
One prominent pathway to sexual intimacy among college student populations is hooking up. Past research has largely compared men and women, with limited attention given to how men differ regarding involvement in hookups and their hookup behaviors. This study used a sample of 412 college men to examine the individual, social, relational, and family background correlates of (1) hooking up during a semester and (2) penetrative hookup encounters (e.g., oral sex, intercourse). Overall, 69% reported a hookup during the semester, with 73% of those who hooked up reporting penetrative hookups. Using logistic regression, men were more likely to hookup if they had an extraverted personality, were consuming more alcohol, and had previous hookup experience. They were less likely to hookup if they were more thoughtful about their relationship decisions and if they were in a stable, committed romantic relationship. Men also were more likely to engage in penetrative hookups only if they held more permissive attitudes towards sex and if they had previous penetrative hookup experience. Implications for intervention and research are discussed.
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Gilda Giebel et al.
Evolutionary Psychology, March 2013, Pages 248-262
Abstract:
Many studies have reported that during high fertility points in the menstrual cycle, women demonstrate increased preference for men with masculinized faces and bodies. In this study, we analyzed whether appetitive aggression in men serves as an additional signal for a favored partner choice. Appetitive aggression describes the intrinsic motivation to act violently even when not being threatened. This study evaluated the responses of 1212 women to one of four descriptions regarding a soldier´s experience after returning from war. The four vignettes included trauma related symptoms with high or low appetitive aggression, or no trauma related symptoms with high or low appetitive aggression. Participants rated their desirability for the soldier in regards to potential long-term and short-term relationships. Results indicate that women preferred a soldier high in appetitive aggression as a short-term mate but not as a long-term relationship. This preference for the "warrior" was higher for women in their fertile window of the menstrual cycle. We conclude that women in their fertile window prefer men exhibiting higher appetitive aggression as a short-term partner, revealing appetitive aggression in men may serve as a signal for a higher genetic fitness.
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Potentials-Attract or Likes-Attract in Human Mate Choice in China
Qiao-Qiao He et al.
PLoS ONE, April 2013
Abstract:
To explain how individuals' self-perceived long-term mate value influences their mate preference and mate choice, two hypotheses have been presented, which are "potentials-attract" and "likes-attract", respectively. The potentials-attract means that people choose mates matched with their sex-specific traits indicating reproductive potentials; and the likes-attract means that people choose mates matched with their own conditions. However, the debate about these two hypotheses still remains unsolved. In this paper, we tested these two hypotheses using a human's actual mate choice data from a Chinese online dating system (called the Baihe website), where 27,183 users of Baihe website are included, in which there are 590 paired couples (1180 individuals) who met each other via the website. Our main results show that not only the relationship between individuals' own attributes and their self-stated mate preference but also that between individuals' own attributes and their actual mate choice are more consistent with the likes-attract hypothesis, i.e., people tend to choose mates who are similar to themselves in a variety of attributes.
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T.K. Saxton et al.
Personality and Individual Differences, forthcoming
Abstract:
An evolutionary approach to attractiveness judgments emphasises that many human trait preferences exist in order to assist adaptive mate choice. Here we test an adaptive development hypothesis, whereby voice pitch preferences indicating potential mate quality might arise or strengthen significantly during adolescence (when mate choice becomes adaptive). We used a longitudinal study of 250 adolescents to investigate changes in preference for voice pitch, a proposed marker of mate quality. We found significantly stronger preferences for lower-pitched opposite-sex voices in the older age group compared with the younger age group (using different sets of age-matched stimuli), and marginally increased preferences for lower-pitched opposite-sex voices comparing within-participant preferences for the same set of stimuli over the course of 1 year. We also found stability in individual differences in preferences across adolescence: controlling for age, the raters who had stronger preferences than their peers for lower-pitched voices when first tested, retained stronger preferences for lower-pitched voices relative to their peers about 1 year later. Adolescence provides a useful arena for evaluating adaptive hypotheses and testing the cues that might give rise to adaptive behaviour.
Friday, April 19, 2013
Flush with cash
What's So Funny about Making Monetary Policy?
Kevin Capehart
Economic Inquiry, forthcoming
Abstract:
During their meetings, the members of the Federal Open Market Committee (FOMC) make monetary policy, but they also make each other laugh. This article studies the amount of laughter elicited by members of the FOMC during their meetings. The study finds that a member elicits more laughter if he or she expects higher inflation, other things being equal. This finding suggests that members may use humor to cope with the threat of inflation.
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Economics versus Politics: Pitfalls of Policy Advice
Daron Acemoglu & James Robinson
NBER Working Paper, March 2013
Abstract:
The standard approach to policy-making and advice in economics implicitly or explicitly ignores politics and political economy, and maintains that if possible, any market failure should be rapidly removed. This essay explains why this conclusion may be incorrect; because it ignores politics, this approach is oblivious to the impact of the removal of market failures on future political equilibria and economic efficiency, which can be deleterious. We first outline a simple framework for the study of the impact of current economic policies on future political equilibria and indirectly on future economic outcomes. We then illustrate the mechanisms through which such impacts might operate using a series of examples. The main message is that sound economic policy should be based on a careful analysis of political economy and should factor in its influence on future political equilibria.
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The Missing Wealth of Nations: Are Europe and the U.S. net Debtors or net Creditors?
Gabriel Zucman
Quarterly Journal of Economics, forthcoming
Abstract:
This paper shows that official statistics substantially underestimate the net foreign asset positions of rich countries because they fail to capture most of the assets held by households in offshore tax havens. Drawing on a unique Swiss dataset and exploiting systematic anomalies in countries' portfolio investment positions, I find that around 8% of the global financial wealth of households is held in tax havens, three-quarters of which goes unrecorded. On the basis of plausible assumptions, accounting for unrecorded assets turns the eurozone, officially the world's second largest net debtor, into a net creditor. It also reduces the U.S. net debt significantly. The results shed new light on global imbalances and challenge the widespread view that, after a decade of poor-to-rich capital flows, external assets are now in poor countries and debts in rich countries. I provide concrete proposals to improve international statistics.
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Government efficiency, institutions, and the effects of fiscal consolidation on public debt
Freddy Heylen, Annelies Hoebeeck & Tim Buyse
European Journal of Political Economy, forthcoming
Abstract:
We study the evolution of the ratio of public debt to GDP during 132 fiscal episodes in 21 OECD countries in 1981-2008. Our main focus is on debt dynamics during 40 consolidation periods. To define these periods we use data on the evolution of the underlying cyclically adjusted primary balance, and as such avoid biases that may be induced by one-off budgetary measures. The paper brings new evidence on the role of public sector efficiency for the success of fiscal consolidation. First, we confirm that consolidation programmes imply a stronger reduction of the public debt ratio when they rely mainly on spending cuts, except public investment. Government wage bill cuts, however, only contribute to lower public debt ratios when public sector efficiency is low. Second, we find that a given consolidation programme will be more effective in bringing down debt when it is adopted by a more efficient government apparatus. Third, more efficient governments adopt consolidation programmes of better composition. As to other institutions, consolidation policies are more successful when they are accompanied by product market deregulation, and when they are adopted by left-wing governments. By contrast, simultaneous labour market deregulation may be counterproductive during consolidation periods.
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Household Leveraging and Deleveraging
Alejandro Justiniano, Giorgio Primiceri & Andrea Tambalotti
NBER Working Paper, April 2013
Abstract:
U.S. households' debt skyrocketed between 2000 and 2007, and has been falling since. This leveraging (and deleveraging) cycle cannot be accounted for by the liberalization, and subsequent tightening, of credit standards in mortgage markets observed during the same period. We base this conclusion on a quantitative dynamic general equilibrium model calibrated using macroeconomic aggregates and microeconomic data from the Survey of Consumer Finances. From the perspective of the model, the credit cycle is more likely due to factors that impacted house prices more directly, thus affecting the availability of credit through a collateral channel. In either case, the macroeconomic consequences of leveraging and deleveraging are relatively minor, because the responses of borrowers and lenders roughly wash out in the aggregate.
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Does High Public Debt Consistently Stifle Economic Growth? A Critique of Reinhart and Rogoff
Thomas Herndon, Michael Ash & Robert Pollin
University of Massachusetts Working Paper, April 2013
Abstract:
We replicate Reinhart and Rogoff (2010a and 2010b) and find that coding errors, selective exclusion of available data, and unconventional weighting of summary statistics lead to serious errors that inaccurately represent the relationship between public debt and GDP growth among 20 advanced economies in the post-war period. Our finding is that when properly calculated, the average real GDP growth rate for countries carrying a public-debt-to-GDP ratio of over 90 percent is actually 2.2 percent, not 0:1 percent as published in Reinhart and Rogoff. That is, contrary to RR, average GDP growth at public debt/GDP ratios over 90 percent is not dramatically different than when debt/GDP ratios are lower. We also show how the relationship between public debt and GDP growth varies significantly by time period and country. Overall, the evidence we review contradicts Reinhart and Rogoff's claim to have identified an important stylized fact, that public debt loads greater than 90 percent of GDP consistently reduce GDP growth.
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Capital Tax Reform and the Real Economy: The Effects of the 2003 Dividend Tax Cut
Danny Yagan
University of California Working Paper, January 2013
Abstract:
Policymakers frequently propose to use capital tax reform to stimulate investment and increase labor earnings. This paper tests for such real impacts of the 2003 dividend tax cut -- one of the largest reforms ever to a U.S. capital tax rate -- using a quasi-experimental design and a large sample of U.S. corporate tax returns from years 1996-2008. I estimate that the tax cut caused zero change in corporate investment, with an upper bound elasticity with respect to one minus the top statutory tax rate of .08 and an upper bound effect size of .03 standard deviations. This null result is robust across specifications, samples, and investment measures. I similarly find no impact on employee compensation. The lack of detectable real effects contrasts with an immediate impact on financial payouts to shareholders. Economically, the findings challenge leading estimates of the cost-of-capital elasticity of investment, or undermine models in which dividend tax reforms affect the cost of capital. Either way, it may be difficult for policymakers to implement an alternative dividend tax cut that has substantially larger near-term effects.
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Shanthi Ramnath
Journal of Public Economics, May 2013, Pages 77-93
Abstract:
This paper uses the Saver's Credit to analyze taxpayers' understanding of, and responses to, tax incentives. The Saver's Credit is a tax credit designed to encourage retirement savings among low and middle income households; however, the credit's structure creates "notches", or discontinuous jumps, within a household's budget constraint. These notches provide an incentive to manipulate adjusted gross income to fall just below the level where the credit decreases. I use Public Use Tax Files from the Internal Revenue Service to test whether taxpayers bunch their income at the notch created by the Saver's Credit. I find strong evidence that bunching occurred in response to the credit, which implies that taxpayers claiming the credit understood the incentives for bunching and indeed manipulated their incomes accordingly. I then exploit the discontinuity in credit rates to analyze the credit's impact on retirement contribution behavior using a regression discontinuity approach, and find thatthe credit failed to generate a statistically significant effect on the level of retirement contributions. These results imply that the Saver's Credit is more effective at providing transfers to low and middle income taxpayers than at increasing retirement contributions.
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Efficient government size: France in the 20th century
François Facchini & Mickaël Melki
European Journal of Political Economy, September 2013, Pages 1-14
Abstract:
The benefits and costs of government suggest an efficient government size. We investigate efficient government size by analysing the relation between public spending and real GDP for France in the period 1896-2008. The results show a co-integration nonlinear relationship. Our time-series data on France represents one of the longest periods studied in literature. Our empirical findings suggest that efficient government size measured by public spending was reached when public spending was around 30% of GDP. Conclusions point to particularities of countries that suggest efficient government size is specific to different countries.
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Finance: Function Matters, not Size
John Cochrane
NBER Working Paper, April 2013
Abstract:
I address the controversy over whether the financial services industry is "too big." We should be asking whether the finance industry is functioning properly instead. The facts suggest that demand for financial services increased, perhaps temporarily, rather than suggesting a changing distortion within the industry. The puzzling persistence of actively managed mutual funds is finally yielding to supply and demand analysis, but the increasing preference for high-fee delegated management by sophisticated institutional investors remains somewhat of a puzzle. Conventional alpha-beta analysis does not capture the rich structure of risk premiums, which active management may be accessing. High-frequency information trading and the price-discovery process remain a puzzle as well. Many "inefficiencies" and events of the financial crisis suggest too little rather than too much active trading. The instability and regulation of the US financial system are more important issues than its mere size.
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Tracing the Link between Government Size and Growth: The Role of Public Sector Quality
Daniel Oto-Peralías & Diego Romero-Ávila
Kyklos, May 2013, Pages 229-255
Abstract:
This paper shows evidence of strong heterogeneity in the relationship between government size and growth, depending on the quality of public sector institutions. Focusing on a wide sample of developed and developing countries over the period 1981-2005, we find that government size reduces growth when bureaucracy quality is low, whereas no significant effect is observed for sufficiently high levels of bureaucracy quality. The results hold both in cross-section and panel data analyses and are robust to a large number of robustness checks. These findings have important implications for assessing the role of government size in economic growth.
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Banking Crises: An Equal Opportunity Menace
Carmen Reinhart & Kenneth Rogoff
Journal of Banking & Finance, forthcoming
Abstract:
The historical frequency of banking crises is similar in advanced and developing countries, with quantitative parallels in both the run-ups and the aftermath. We establish these regularities using a dataset spanning from the early 1800s to the present. Banking crises weaken fiscal positions, with government revenues invariably contracting. Three years after a crisis central government debt increases by about 86 percent. The fiscal burden of banking crisis extends beyond the cost of the bailouts. We find that systemic banking crises are typically preceded by asset price bubbles, large capital inflows and credit booms, in rich and poor countries alike.
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Shifting Mandates: The Federal Reserve's First Centennial
Carmen Reinhart & Kenneth Rogoff
NBER Working Paper, March 2013
Abstract:
The mandate of the Federal Reserve has evolved considerably over its hundred-year history. From an initial focus in 1913 on financial stability, to fiscal financing in World War II and its aftermath, to a strong anti-inflation focus from the late 1970s, and then back to greater emphasis on financial stability since the Great Contraction. Yet, as the Fed's mandate has expanded in recent years, its range of instruments has narrowed, partly based on a misguided belief in the inherent stability of financial markets. We briefly discuss the active use in an earlier era of multiple instruments, including reserve requirements, credit controls and interest rate ceilings.
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Uncertainty and Economic Activity: Evidence from Business Survey Data
Rüdiger Bachmann, Steffen Elstner & Eric Sims
American Economic Journal: Macroeconomics, April 2013, Pages 217-249
Abstract:
This paper uses survey expectations data to construct empirical proxies for time-varying business-level uncertainty. Access to the micro data from the German IFO Business Climate Survey permits construction of uncertainty measures based on both ex ante disagreement and ex post forecast errors. Ex ante disagreement is strongly correlated with dispersion in ex post forecast errors. Surprise movements in either measure lead to significant reductions in production that abate fairly quickly. We extend our analysis to US data, measuring uncertainty with forecast disagreement from the Business Outlook Survey. Surprise increases in forecast dispersion lead to more persistent reductions in production than in the German data.
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Soft information and economic activity: Evidence from the Beige Book
Shibley Sadique et al.
Journal of Macroeconomics, forthcoming
Abstract:
This study employs text-analysis software to analyze the contents of the Federal Reserve Beige Book summary of national economic and business conditions, with a particular focus on the predictive content of the text. We show that the Beige Book language is a good predictor of economic turning points as it often provides an early indication of future economic activities. During economic upswings, positive tone becomes more prominent and negative tone becomes less prominent. In addition, this study is the first to document that Beige Book tone affects stock market volatility and trading volume.
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The value of honesty: Empirical estimates from the case of the missing children
Sara LaLumia & James Sallee
International Tax and Public Finance, April 2013, Pages 192-224
Abstract:
How much are people willing to forego to be honest, to follow the rules? When people do break the rules, what can standard data sources tell us about their behavior? Standard economic models of crime typically assume that individuals are indifferent to dishonesty, so that they will cheat or lie as long as the expected pecuniary benefits exceed the expected costs of being caught and punished. We investigate this presumption by studying the response to a change in tax reporting rules that made it much more difficult for taxpayers to evade taxes by inappropriately claiming additional dependents. The policy reform induced a substantial reduction in the number of dependents claimed, which indicates that many filers had been cheating before the reform. Yet, the number of filers who availed themselves of this evasion opportunity is dwarfed by the number of filers who passed up substantial tax savings by not claiming extra dependents. By declining the opportunity to cheat, these taxpayers reveal information about their willingness to pay to be honest. In our analysis, we develop a novel method for inferring the characteristics of taxpayers in the absence of audit data. Our findings indicate both that this willingness to pay to be honest is large on average and that it varies significantly across the population of taxpayers.
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Are Household Surveys Like Tax Forms? Evidence from Income Underreporting of the Self-Employed
Erik Hurst, Geng Li & Benjamin Pugsley
Review of Economics and Statistics, forthcoming
Abstract:
There is a large literature showing that the self-employed underreport their income to tax authorities. In this paper, we quantify the extent to which the self-employed also systematically underreport their income in U.S. household surveys. We use the Engel curve describing the relationship between income and expenditures of wage and salary workers to infer the actual income, and thus the reporting gap, of the self-employed based on their reported expenditures. On average, the self-employed underreport their income by about 25 percent. We show that failing to account for such income underreporting leads to biased conclusions in a variety of settings.
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The End Of Bank Secrecy? An Evaluation Of The G20 Tax Haven Crackdown
Niels Johannesen & Gabriel Zucman
American Economic Journal: Economic Policy, forthcoming
Abstract:
During the financial crisis, G20 countries compelled tax havens to sign bilateral treaties providing for exchange of bank information. Policymakers have celebrated this global initiative as the end of bank secrecy. Exploiting a unique panel dataset, our study is the first attempt to assess how the treaties affected bank deposits in tax havens. Rather than repatriating funds, our results suggest that tax evaders shifted deposits to havens not covered by a treaty with their home country. The crackdown thus caused a relocation of deposits at the benefit of the least compliant havens. We discuss the policy implications of these findings.
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Do private sector forecasters chase after IMF or OECD forecasts?
Michael Frenkel, Jan-Christoph Rülke & Lilli Zimmermann
Journal of Macroeconomics, forthcoming
Abstract:
In this paper we use data from the Consensus Economics forecast poll to explore the strategic behavior of private sector forecasters with respect to forecasts published by the IMF and the OECD. We focus on four key macroeconomic variables for the G7 countries to analyze whether private sector forecasters herd towards the projections published by these international organizations. Our empirical results show that an anti-herding strategy of private sector forecasters is prevalent for the G7 countries, i.e. they intentionally place their forecasts away from the forecasts published by the IMF and the OECD. In addition, we find that the strategic behavior of private sector forecasters lasts roughly three months.
Thursday, April 18, 2013
Let's do it
Rethinking the Extraverted Sales Ideal: The Ambivert Advantage
Adam Grant
Psychological Science, forthcoming
Abstract:
Despite the widespread assumption that extraverts are the most productive salespeople, research has shown weak and conflicting relationships between extraversion and sales performance. In light of these puzzling results, I propose that the relationship between extraversion and sales performance is not linear but curvilinear: Ambiverts achieve greater sales productivity than extraverts or introverts do. Because they naturally engage in a flexible pattern of talking and listening, ambiverts are likely to express sufficient assertiveness and enthusiasm to persuade and close a sale but are more inclined to listen to customers' interests and less vulnerable to appearing too excited or overconfident. A study of 340 outbound-call-center representatives supported the predicted inverted-U-shaped relationship between extraversion and sales revenue. This research presents a fresh perspective on the personality traits that facilitate successful influence and offers novel insights for people in choosing jobs and for organizations in hiring and training employees.
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Hajo Adam & Aiwa Shirako
Journal of Applied Psychology, forthcoming
Abstract:
The influence of culture on the social effects of emotions in negotiations has recently gained the attention of researchers, but to date this research has focused exclusively on the cultural background of the perceiver of the emotion expression. The current research offers the first investigation of how the cultural background of the expresser influences negotiation outcomes. On the basis of the stereotype that East Asians are emotionally inexpressive and European Americans are emotionally expressive, we predicted that anger will have a stronger signaling value when East Asians rather than European American negotiators express it. Specifically, we predicted that angry East Asian negotiators will be perceived as tougher and more threatening and therefore elicit great cooperation from counterparts compared with angry European American negotiators. Results from 4 negotiation studies supported our predictions. In Study 1, angry East Asian negotiators elicited greater cooperation than angry European American and Hispanic negotiators. In Study 2, angry East Asian negotiators elicited greater cooperation than angry European American ones, but emotionally neutral East Asian and European American negotiators elicited the same level of cooperation. Study 3 showed that this effect holds for both East Asian and European American perceivers and that it is mediated by angry East Asian negotiators being perceived as tougher and more threatening than angry European American negotiators. Finally, Study 4 demonstrated that the effect emerges only when negotiators hold the stereotype of East Asians being emotionally inexpressive and European Americans being emotionally expressive. We discuss implications for our understanding of culture, emotions, and negotiations.
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Communicating With the Crowd: Speakers Use Abstract Messages When Addressing Larger Audiences
Priyanka Joshi & Cheryl Wakslak
Journal of Experimental Psychology: General, forthcoming
Abstract:
Audience characteristics often shape communicators' message framing. Drawing from construal level theory, we suggest that when speaking to many individuals, communicators frame messages in terms of superordinate characteristics that focus attention on the essence of the message. On the other hand, when communicating with a single individual, communicators increasingly describe events and actions in terms of their concrete details. Using different communication tasks and measures of construal, we show that speakers communicating with many individuals, compared with 1 person, describe events more abstractly (Study 1), describe themselves as more trait-like (Study 2), and use more desirability-related persuasive messages (Study 3). Furthermore, speakers' motivation to communicate with their audience moderates their tendency to frame messages based on audience size (Studies 3 and 4). This audience-size abstraction effect is eliminated when a large audience is described as homogeneous, suggesting that people use abstract construal strategically in order to connect across a disparate group of individuals (Study 5). Finally, we show that participants' experienced fluency in communication is influenced by the match between message abstraction and audience size (Study 6).
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Alex Rutherford et al.
Proceedings of the National Academy of Sciences, 16 April 2013, Pages 6281-6286
Abstract:
The Internet and social media have enabled the mobilization of large crowds to achieve time-critical feats, ranging from mapping crises in real time, to organizing mass rallies, to conducting search-and-rescue operations over large geographies. Despite significant success, selection bias may lead to inflated expectations of the efficacy of social mobilization for these tasks. What are the limits of social mobilization, and how reliable is it in operating at these limits? We build on recent results on the spatiotemporal structure of social and information networks to elucidate the constraints they pose on social mobilization. We use the DARPA Network Challenge as our working scenario, in which social media were used to locate 10 balloons across the United States. We conduct high-resolution simulations for referral-based crowdsourcing and obtain a statistical characterization of the population recruited, geography covered, and time to completion. Our results demonstrate that the outcome is plausible without the presence of mass media but lies at the limit of what time-critical social mobilization can achieve. Success relies critically on highly connected individuals willing to mobilize people in distant locations, overcoming the local trapping of diffusion in highly dense areas. However, even under these highly favorable conditions, the risk of unsuccessful search remains significant. These findings have implications for the design of better incentive schemes for social mobilization. They also call for caution in estimating the reliability of this capability.
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Trash talk in a competitive setting: Impact on self-efficacy and affect
Ben Conmy et al.
Journal of Applied Social Psychology, forthcoming
Abstract:
The effects of trash talk and competition outcome on self-efficacy and affect were examined in 40 MaddenTM NFL 08 football video game players randomly assigned to two conditions: silence talk, where they played the first game in complete silence; and the second trash talking. Measures of self-efficacy, positive affect (PA), and negative affect (NA) were administered. Results revealed that players enforced to be silent in the first game instantaneously exhibited lower self-efficacy, lower PA, and higher NA than players permitted to talk in Game 1. However, players subsequently instructed to remain silent in the second game showed markedly decreased self-efficacy compared to players permitted to talk in Game 2. Results are interpreted in light of the social-cognitive-motivational theory.
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Evidence for utilitarian motives in emotion regulation
Maya Tamir, Brett Ford & Margaret Gilliam
Cognition & Emotion, Spring 2013, Pages 483-491
Abstract:
This investigation demonstrates that emotion regulation can be driven by considerations of utility per se. We show that as participants prepared for a negotiation, those who were motivated to confront (vs. collaborate with) another person believed that anger would be more useful to them. However, only participants who were motivated to confront another and expected to receive a monetary reward for their performance (i.e., high utility), were motivated to increase their anger in preparation for the negotiation. Participants who were motivated to confront another but did not expect their performance to be rewarded (i.e., low utility), did not try to increase their anger, even though they expected anger to be useful in the negotiation. Such patterns demonstrate that people are motivated to experience even unpleasant emotions to maximise utility.
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Repeating "Yes" in a First Request and Compliance with a Later Request: The Four Walls Technique
Nicolas Guéguen et al.
Social Behavior and Personality, March 2013, Pages 199-202
Abstract:
The commitment/consistency principle for compliance implies that people act in ways consistent with their previous behavior. Cialdini and Sagarin (2005) have stated that, according to this principle, asking individuals questions to which they would be expected to say "yes" could be associated with achieving greater compliance with a subsequent request. However, this procedure, referred to as the four walls technique, has never been tested experimentally. In this study, we conducted an experiment in which participants were first asked to answer several questions that required "yes" or "no" responses. Then, the participants were asked to comply with an additional request. It was found that saying "yes" several times beforehand is associated with greater compliance with a subsequent request than is saying "no" beforehand or when no first request was made.
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Nicolas Guéguen et al.
Journal of Applied Social Psychology, January 2013, Pages 116-137
Abstract:
The "evoking freedom" technique is a verbal compliance procedure that solicits someone to comply with a request by simply telling them they are free to accept or to refuse the request. The measure of the efficiency of this technique on compliance with large samples and the evaluation of its influence on various requests was tested in the first set of experiments. This technique was found to be efficient in increasing the number of people who agreed to give money to a requester, the number of smokers who agreed to give a cigarette, passersby who agreed to respond to a survey, and homeowners who agreed to buy pancakes. In the second set of experiments in which the mode of interaction between the requester and the person solicited was tested, the "evoking freedom" technique was found to be associated with greater compliance with a request addressed by mail and through face-to-face, phone-to-phone, or computer-mediated interaction. The third set of experiments tested the effect of semantic variations of the "evoking freedom" technique and the weight of the repetition of the semantic evocation of freedom. These later experiments that used various phrases evoking the freedom to comply were found to be associated with greater compliance. Moreover, a double evocation of freedom was associated with even greater compliance than a single evocation. The importance of this technique for commitment communication is discussed.
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How activating cognitive content shapes trust: A subliminal priming study
Ann-Christin Posten, Axel Ockenfels & Thomas Mussweiler
Journal of Economic Psychology, forthcoming
Abstract:
The activation of cognitive contents plays a prominent role in social psychological research. Yet, so far this has received little attention in economics. In our research we connect a standard social psychological manipulation to activate cognitive content (a trust vs. distrust priming manipulation) to a classic paradigm from economics (a trust game). Our findings demonstrate that subliminally activating the concept of trust (vs. distrust) leads participants to judge a series of strangers as more (vs. less) trustworthy. Moreover, our research shows for the first time that such a subliminal priming manipulation shapes the subsequent sending behavior in a fictitious version of a standard economic trust game. This suggests that psychological priming techniques allow new insights into what determines beliefs in economic games.
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Aaron Halfaker et al.
American Behavioral Scientist, May 2013, Pages 664-688
Abstract:
Open collaboration systems, such as Wikipedia, need to maintain a pool of volunteer contributors to remain relevant. Wikipedia was created through a tremendous number of contributions by millions of contributors. However, recent research has shown that the number of active contributors in Wikipedia has been declining steadily for years and suggests that a sharp decline in the retention of newcomers is the cause. This article presents data that show how several changes the Wikipedia community made to manage quality and consistency in the face of a massive growth in participation have ironically crippled the very growth they were designed to manage. Specifically, the restrictiveness of the encyclopedia's primary quality control mechanism and the algorithmic tools used to reject contributions are implicated as key causes of decreased newcomer retention. Furthermore, the community's formal mechanisms for norm articulation are shown to have calcified against changes - especially changes proposed by newer editors.
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Benjamin Tabak et al.
Social Cognitive and Affective Neuroscience, forthcoming
Abstract:
Variations in the gene that encodes the oxytocin receptor (OXTR) have been associated with many aspects of social cognition as well as several prosocial behaviors. However, potential associations of OXTR variants with reactions to betrayals of trust while cooperating for mutual benefit have not yet been explored. We examined how variation in 10 SNPs on OXTR were associated with behavior and emotional reactions following a betrayal of trust in an iterated prisoner's dilemma game. After correction for multiple testing, one haplotype (C-rs9840864, T-rs2268494) was significantly associated with faster retaliation post-betrayal - an association that appeared to be due to this haplotype's intermediate effect of exacerbating people's anger after they had been betrayed. Furthermore, one haplotype (A-rs237887, C-rs2268490) was associated with higher levels of post-betrayal satisfaction, and a third haplotype (G-rs237887, C-rs2268490) was associated with lower levels of post-betrayal satisfaction.
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Generous economic investments after basolateral amygdala damage
Jack van Honk et al.
Proceedings of the National Academy of Sciences, 12 February 2013, Pages 2506-2510
Abstract:
Contemporary economic models hold that instrumental and impulsive behaviors underlie human social decision making. The amygdala is assumed to be involved in social-economic behavior, but its role in human behavior is poorly understood. Rodent research suggests that the basolateral amygdala (BLA) subserves instrumental behaviors and regulates the central-medial amygdala, which subserves impulsive behaviors. The human amygdala, however, typically is investigated as a single unit. If these rodent data could be translated to humans, selective dysfunction of the human BLA might constrain instrumental social-economic decisions and result in more impulsive social-economic choice behavior. Here we show that humans with selective BLA damage and a functional central-medial amygdala invest nearly 100% more money in unfamiliar others in a trust game than do healthy controls. We furthermore show that this generosity is not caused by risk-taking deviations in nonsocial contexts. Moreover, these BLA-damaged subjects do not expect higher returns or perceive people as more trustworthy, implying that their generous investments are not instrumental in nature. These findings suggest that the human BLA is essential for instrumental behaviors in social-economic interactions.
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More Trusting, Less Trust? An Investigation of Early E-Commerce in China
Hongbin Cai et al.
NBER Working Paper, April 2013
Abstract:
Trust is vital for market development, but how can trust be enhanced in a marketplace? A common view is that more trusting may help to build trust, especially in less developed economies. In this paper, we argue that more trusting may lead to less trust. We set up a rational expectation model in which a marketplace uses buyer protection to promote buyer trusting. Our results show that buyer protection may reduce trust in equilibrium and even hinder market expansion because it triggers differential entry between honest and strategic sellers and may induce more cheating from strategic sellers. Using a large transaction-level data set from the early years of Eachnet.com (an eBay equivalent in China), we find evidence that is consistent with the model predictions. Stronger buyer protection leads to less favorable evaluation of seller behavior and is associated with slower market expansion. These findings suggest that a trust-promoting policy aiming at buyer trusting may not be effective if it is not accompanied by additional incentives to improve seller trustworthiness.
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Implicit vs. explicit deception in ultimatum games with incomplete information
Peter Kriss, Rosemarie Nagel & Roberto Weber
Journal of Economic Behavior & Organization, forthcoming
Abstract:
We explore bargaining, using ultimatum games, when one party, the proposer, possesses private information about the pie size and can either misrepresent this information through untruthful statements (explicit deception) or through information-revealing actions (implicit deception). Our study is the first such direct comparison between two ways in which people can deceive. We find that requiring informed parties to make an explicit statement yields greater deception than when information is communicated implicitly, particularly for larger stakes. However, allowing the explicit statement to be accompanied by a promise of truthfulness reverses this effect. In contrast with many previous studies, we generally observe very high frequencies of dishonesty.
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Competition over Personal Resources Favors Contribution to Shared Resources in Human Groups
Jessica Barker, Pat Barclay & Kern Reeve
PLoS ONE, March 2013
Abstract:
Members of social groups face a trade-off between investing selfish effort for themselves and investing cooperative effort to produce a shared group resource. Many group resources are shared equitably: they may be intrinsically non-excludable public goods, such as vigilance against predators, or so large that there is little cost to sharing, such as cooperatively hunted big game. However, group members' personal resources, such as food hunted individually, may be monopolizable. In such cases, an individual may benefit by investing effort in taking others' personal resources, and in defending one's own resources against others. We use a game theoretic "tug-of-war" model to predict that when such competition over personal resources is possible, players will contribute more towards a group resource, and also obtain higher payoffs from doing so. We test and find support for these predictions in two laboratory economic games with humans, comparing people's investment decisions in games with and without the options to compete over personal resources or invest in a group resource. Our results help explain why people cooperatively contribute to group resources, suggest how a tragedy of the commons may be avoided, and highlight unifying features in the evolution of cooperation and competition in human and non-human societies.
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There's no "I" in team: Effects of cooperative video games on cooperative behavior
Tobias Greitemeyer & Christopher Cox
European Journal of Social Psychology, April 2013, Pages 224-228
Abstract:
The present research tests the idea that playing a team-player video game in which players work together as teammates and assist each other in achieving a common goal increases cooperative behavior toward a new partner. In fact, relative to a single-player mode, cooperatively playing a video game increased cooperation in a mixed-motive decision dilemma task. Because the players were exposed to the same video game content in both experimental conditions, the effect on cooperative behavior can only be accounted for by the different way the game was played. Mediation analyses revealed that cooperative team play promoted feelings of cohesion, which activated trust (i.e., the expectation of reciprocal cooperation), which in turn increased cooperative behavior.
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Disclosing Advisor's Interests Neither Hurts Nor Helps
Huseyn Ismayilov & Jan Potters
Journal of Economic Behavior & Organization, forthcoming
Abstract:
We set up an experiment to study whether disclosure of the advisor's interests can foster truthfulness and trust. We measure how advisors expect decisionmakers to react to their advice in order to distinguish between strategic and moral reactions to disclosure by advisors. Results indicate that advisors do not expect decision makers to react drastically to disclosure. Also, advisors do not find deceiving morally more acceptable with disclosure than with no disclosure. Overall, disclosure neither hurts nor helps; deceptive advice and mistrust are equally frequent with as without disclosure.
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Julie Novakova & Jaroslav Flegr
PLoS ONE, April 2013
Background: The aim of this study was to determine whether people respond differently to low and high stakes in Dictator and Ultimatum Games. We assumed that if we raised the stakes high enough, we would observe more self-orientated behavior because fairness would become too costly, in spite of a possible risk of a higher punishment.
Methods: A questionnaire was completed by a sample of 524 university students of biology. A mixed linear model was used to test the relation between the amount at stake (CZK 20, 200, 2,000, 20,000 and 200,000, i.e., approximately $1-$10,000) and the shares, as well as the subjects' gender and the design of the study (single vs. multiple games for different amounts).
Results: We have discovered a significant relationship between the amount at stake and the minimum acceptable offer in the Ultimatum Game and the proposed shares in both Ultimatum and Dictator Games (p = 0.001, p<0.001, p = 0.0034). The difference between playing a single game or more games with several amounts at stake did not influence the relation between the stakes and the offered and minimum acceptable shares. Women proved significantly more generous than men in their offers in the Dictator Game (p = 0.007).
Conclusion: Our results suggest that people's behavior in the Dictator and Ultimatum Games depends on the amount at stake. The players tended to lower their relative proposed shares, as well as their relative minimum acceptable offers. We propose that the Responders' sense of equity and fair play depends on the stakes because of the costs of maintaining fairness. However, our results also suggest that the price of fairness is very high and that it is very difficult, probably even impossible, to buy the transition of Homo sociologicus into Homo economicus.
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The Development of Trust and Altruism During Childhood
Anthony Evans, Ursula Athenstaedt & Joachim Krueger
Journal of Economic Psychology, June 2013, Pages 82-95
Abstract:
Knowing when to trust is an essential skill, but little is known about its cognitive development. No previous studies have examined the development of trust while controlling for age differences in altruism. We hypothesized that older children are more likely to trust, and that this age-related increase is not due to an increase in altruism. In two experiments, we compared the choices of kindergarten (4-5 years) and elementary school (9-10 years) children in economic games. Age was positively related to both trust and altruism, but more strongly to the former. The age difference in trust was robust when we controlled for partner age and the ability to delay gratification. We further hypothesized that older children are more attuned to the probability of reciprocity. Indeed, older children were more sensitive to changes in the game's structure and the trustee's characteristics, suggesting that they are not only more trusting, but more discerning in their decisions of when to trust.
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Intelligence and Bribing Behavior in a One-Shot Game
Philip Shaw, William Vásquez & Mark LeClair
Journal of Socio-Economics, June 2013, Pages 91-96
Abstract:
We investigate the relationship between intelligence and bribing behavior in a simple one-shot game of corruption. We find a robust relationship between intelligence and the probability of bribing in which a higher intelligence quotient (IQ) leads to a lower probability of bribing in the game. This result holds after controlling for other determinants such as gender, attitude towards corruption, and perceptions of corruption. By revealing the gender of the matched player, we also show that gender perceptions of corruption are strong determinants of bribery.
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Individual heterogeneity and costly punishment: A volunteer's dilemma
Wojtek Przepiorka & Andreas Diekmann
Proceedings of the Royal Society: Biological Sciences, 22 May 2013
Abstract:
Social control and the enforcement of social norms glue a society together. It has been shown theoretically and empirically that informal punishment of wrongdoers fosters cooperation in human groups. Most of this research has focused on voluntary and uncoordinated punishment carried out by individual group members. However, as punishment is costly, it is an open question as to why humans engage in the punishment of wrongdoers even in one-time-only encounters. While evolved punitive preferences have been advocated as proximate explanations for such behaviour, the strategic nature of the punishment situation has remained underexplored. It has been suggested to conceive of the punishment situation as a volunteer's dilemma (VOD), where only one individual's action is necessary and sufficient to punish the wrongdoer. Here, we show experimentally that implementing the punishment situation as a VOD sustains cooperation in an environment where punishers and non-punishers coexist. Moreover, we show that punishment-cost heterogeneity allows individuals to tacitly agree on only the strongest group member carrying out the punishment, thereby increasing the effectiveness and efficiency of social norm enforcement. Our results corroborate that costly peer punishment can be explained without assuming punitive preferences and show that centralized sanctioning institutions can emerge from arbitrary individual differences.
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Mareike Hoffmann, Thomas Lauer & Bettina Rockenbach
Journal of Economic Behavior & Organization, forthcoming
Abstract:
According to the Greek philosopher Plato "[...] if anyone at all is to have the privilege of lying the rulers of the State [...] may be allowed to lie for the public good" (The Royal Lie). To investigate whether The Royal Lie may foster cooperation in public goods provision we experimentally study centralized manipulations of contribution feedback. We find that a uniform feedback exaggeration does not increase cooperation and is disapproved once it is disclosed. An individual exaggeration, however, that gives nobody the feeling of being a sucker sustains cooperation on a high level.
Wednesday, April 17, 2013
Job numbers
The Great Reversal in the Demand for Skill and Cognitive Tasks
Paul Beaudry, David Green & Benjamin Sand
NBER Working Paper, March 2013
Abstract:
What explains the current low rate of employment in the US? While there has been substantial debate over this question in recent years, we believe that considerable added insight can be derived by focusing on changes in the labor market at the turn of the century. In particular, we argue that in about the year 2000, the demand for skill (or, more specifically, for cognitive tasks often associated with high educational skill) underwent a reversal. Many researchers have documented a strong, ongoing increase in the demand for skills in the decades leading up to 2000. In this paper, we document a decline in that demand in the years since 2000, even as the supply of high education workers continues to grow. We go on to show that, in response to this demand reversal, high-skilled workers have moved down the occupational ladder and have begun to perform jobs traditionally performed by lower-skilled workers. This de-skilling process, in turn, results in high-skilled workers pushing low-skilled workers even further down the occupational ladder and, to some degree, out of the labor force all together. In order to understand these patterns, we offer a simple extension to the standard skill biased technical change model that views cognitive tasks as a stock rather than a flow. We show how such a model can explain the trends in the data that we present, and offers a novel interpretation of the current employment situation in the US.
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Christopher Hsee et al.
Psychological Science, forthcoming
Abstract:
High productivity and high earning rates brought about by modern technologies make it possible for people to work less and enjoy more, yet many continue to work assiduously to earn more. Do people overearn - forgo leisure to work and earn beyond their needs? This question is understudied, partly because in real life, determining the right amount of earning and defining overearning are difficult. In this research, we introduced a minimalistic paradigm that allows researchers to study overearning in a controlled laboratory setting. Using this paradigm, we found that individuals do overearn, even at the cost of happiness, and that overearning is a result of mindless accumulation - a tendency to work and earn until feeling tired rather than until having enough. Supporting the mindless-accumulation notion, our results show, first, that individuals work about the same amount regardless of earning rates and hence are more likely to overearn when earning rates are high than when they are low, and second, that prompting individuals to consider the consequences of their earnings or denying them excessive earnings can disrupt mindless accumulation and enhance happiness.
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Martin Obschonka et al.
Journal of Personality and Social Psychology, forthcoming
Abstract:
In recent years the topic of entrepreneurship has become a major focus in the social sciences, with renewed interest in the links between personality and entrepreneurship. Taking a socioecological perspective to psychology, which emphasizes the role of social habitats and their interactions with mind and behavior, we investigated regional variation in and correlates of an entrepreneurship-prone Big Five profile. Specifically, we analyzed personality data collected from over half a million U.S. residents (N = 619,397) as well as public archival data on state-level entrepreneurial activity (i.e., business-creation and self-employment rates). Results revealed that an entrepreneurship-prone personality profile is regionally clustered. This geographical distribution corresponds to the pattern that can be observed when mapping entrepreneurial activity across the United States. Indeed, the state-level correlation (N = 51) between an entrepreneurial personality structure and entrepreneurial activity was positive in direction, substantial in magnitude, and robust even when controlling for regional economic prosperity. These correlations persisted at the level of U.S. metropolitan statistical areas (N = 15) and were replicated in independent German (N = 19,842; 14 regions) and British (N = 15,617; 12 regions) samples. In contrast to these profile-based analyses, an analysis linking the individual Big Five dimensions to regional measures of entrepreneurial activity did not yield consistent findings. Discussion focuses on the implications of these findings for interdisciplinary theory development and practical applications.
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Inefficient Hiring in Entry-Level Labor Markets
Amanda Pallais
NBER Working Paper, March 2013
Abstract:
Hiring inexperienced workers generates information about their abilities. If this information is public, workers obtain its benefits. If workers cannot compensate firms for hiring them, firms will hire too few inexperienced workers. I determine the effects of hiring workers and revealing more information about their abilities through a field experiment in an online marketplace. I hired 952 randomly-selected workers, giving them either detailed or coarse public evaluations. Both hiring workers and providing more detailed evaluations substantially improved workers' subsequent employment outcomes. Under plausible assumptions, the experiment's market-level benefits exceeded its cost, suggesting that some experimental workers had been inefficiently unemployed.
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Minimum Wage Increases in a Recessionary Environment
John Addison, McKinley Blackburn & Chad Cotti
Labour Economics, August 2013, Pages 30-39
Abstract:
Do seemingly large minimum-wage increases in an environment of deep recession produce clearer evidence of disemployment than is often observed in the modern minimum wage literature? This paper uses three data sets to examine the employment effects of the most recent increases in the U.S. minimum wage. We focus on two high-risk groups - restaurant-and-bar employees and teenagers - for the years 2005-2010. Although the evidence for a general disemployment effect is not uniform, estimates do suggest the presence of a negative minimum wage effect in states hardest hit by the recession.
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Manufacturing Decline, Housing Booms, and Non-Employment
Kerwin Kofi Charles, Erik Hurst & Matthew Notowidigdo
NBER Working Paper, April 2013
Abstract:
We assess the extent to which manufacturing decline and housing booms contributed to changes in U.S. non-employment during the 2000s. Using a local labor market design, we estimate that manufacturing decline significantly increased non-employment during 2000-2007, while local housing booms decreased non-employment by roughly the same magnitude. The effects of manufacturing decline persist through 2011, but we find no persistent non-employment effects of local housing booms, most plausibly because housing booms were associated with subsequent busts of similar magnitude. We also find that housing booms significantly reduce the likelihood that displaced manufacturing workers remain non-employed, suggesting that housing booms "mask" non-employment growth that would have otherwise occurred earlier in the absence of the booms. Applying our estimates to the national labor market, we find that housing booms reduced non-employment growth by roughly 30 percent during 2000-2007 and that roughly 40 percent of the aggregate increase in non-employment during 2000-2011 can be attributed to manufacturing decline. Collectively, our results suggest that much of the non-employment growth during the 2000s can be attributed to manufacturing decline and these effects would have appeared in aggregate statistics earlier had it not been for the large, temporary increases in housing demand.
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The Impact of Minimum Wages on Labour Market Transitions
Pierre Brochu & David Green
Economic Journal, forthcoming
Abstract:
We investigate differences in labour market transition rates between high and low minimum wage regimes using Canadian data spanning 1979 to 2008. We find that higher minimum wages result in lower hiring rates but also lower job separation rates. Importantly, the reduced separation rates are due mainly to reductions in layoffs, occur in the first 6 months of a job, and are present for unskilled workers of all ages. Thus, jobs in higher minimum wage regimes are more stable but harder to get. For older workers, these effects are almost exactly offsetting, resulting in little impact on the employment rate.
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Local Deficits and Local Jobs: Can U.S. States Stabilize Their Own Economies?
Gerald Carlino & Robert Inman
NBER Working Paper, March 2013
Abstract:
Using a sample of the 48 mainland U.S. states for the period 1973-2009, we study the ability of U.S. states to expand own state employment through the use of state deficit policies. The analysis allows for the facts that U.S. states are part of a wider monetary and economic union with free factor mobility across all states and that state residents and firms may purchase goods from "neighboring" states. Those purchases may generate economic spillovers across neighbors. Estimates suggest that states can increase own state employment by increasing their own deficits. There is evidence of spillovers to employment in neighboring states defined by common cyclical patterns among state economies. For large states, aggregate spillovers to its economic neighbors are approximately two-thirds of own state job growth. Because of significant spillovers and possible incentives to free-ride, there is a potential case to actively coordinate (i.e., centralize) the management of stabilization policies. Finally, job effects of a temporary increase in state own deficits persist for at most one to two years and there is evidence of negative job effects when these deficits are scheduled for repayment.
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Spillovers from High-Skill Consumption to Low-Skill Labor Markets
Francesca Mazzolari & Giuseppe Ragusa
Review of Economics and Statistics, March 2013, Pages 74-86
Abstract:
The least-skilled workforce in the United States is disproportionally employed in the provision of time-intensive services that can be thought of as market substitutes for home production activities. At the same time, skilled workers, with their high opportunity cost of time, spend a larger fraction of their budget in these services. Given the skill asymmetry between consumers and providers in this market, product demand shifts - such as those arising when relative skilled wages increase - should boost relative labor demand for the least-skilled workforce. We estimate that this channel may explain one-third of the growth of employment of noncollege workers in low-skill services in the 1990s.
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Targeted Business Incentives and Local Labor Markets
Matthew Freedman
Journal of Human Resources, Spring 2013, Pages 311-344
Abstract:
This paper uses a regression discontinuity design to examine the effects of geographically targeted business incentives on local labor markets. Unlike elsewhere in the United States, enterprise zone (EZ) designations in Texas are determined in part by a cutoff rule based on census block group poverty rates. Exploiting this discontinuity as a source of quasi-experimental variation in investment and hiring incentives across areas, I find that EZ designation has a positive effect on resident employment, increasing opportunities mainly in lower-paying industries. While business sitings spurred by the program are more geographically diffuse, EZ designation is associated with increases in home values.
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House Prices, Collateral and Self-Employment
Manuel Adelino, Antoinette Schoar & Felipe Severino
NBER Working Paper, March 2013
Abstract:
This paper documents the role of the collateral lending channel to facilitate small business starts and self-employment in the period before the financial crisis of 2008. We document that between 2002 and 2007 areas with a bigger run up in house prices experienced a strong increase in employment in small businesses compared to employment in large firms in the same industries. This increase in small business employment was particularly pronounced in (1) industries that need little startup capital and can thus more easily be financed out of increases in housing as collateral; (2) manufacturing industries where goods are shipped over long distances, which rules out that local demand is driving the expansion. We show that this effect is separate from an aggregate demand channel that relies on home equity based borrowing leading to increased demand and employment creation.
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The Impact of Business Cycle Fluctuations on Graduate School Enrollment
Matthew Johnson
Economics of Education Review, June 2013, Pages 122-134
Abstract:
This paper adds to the understanding of student decisions about graduate school attendance by studying the magnitude of the effect of business cycle fluctuations on enrollment. I use data on graduate school enrollment from the Current Population Survey and statewide variation in unemployment rates across time to proxy for changes in business cycle conditions. I find that overall graduate school enrollment is countercyclical for females and acyclical for males. I show that changes in the unemployment rate have non-linear impacts on female enrollment and that poor labor market conditions lead to a substitution from full-time enrollment to part-time enrollment for both genders.
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Matthew Bidwell
Organization Science, forthcoming
Abstract:
Recent declines in the average length of time that U.S. workers spend with a given employer represent an important change in the nature of the employment relationship, yet it is one whose causes are poorly understood. I explore those causes using Current Population Survey data on the tenure of men aged 30-65, from the years 1979-2008. I argue that long-term employment relationships primarily occur when workers pressure employers to close off employment from market competition, reducing the attractiveness of external mobility relative to internal opportunities and increasing employment security. I then explore how two changes in organizations' environments - a decline in union strength and increased turbulence from changes in technology and globalization - might have affected workers' ability to secure such closed employment relationships over the last 30 years. My results support the argument that declines in tenure reflect the reduced power of workers to secure closed employment relationships. Recent declines in tenure have been concentrated in large organizations, and many of those declines are explained by controlling for the changing levels of industry unionization. I find little evidence that foreign competition or technological change affected mobility. The results are robust to measures of changing industry growth rates and within-industry reorganization. Supplementary analyses suggest that layoffs are associated with different industry pressures than tenure and that voluntary mobility may have played an important role in declines in tenure.
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The Employment Effects of State Hiring Credits During and After the Great Recession
David Neumark & Diego Grijalva
NBER Working Paper, March 2013
Abstract:
State and federal policymakers grappling with the aftermath of the Great Recession have sought ways to spur job creation, in many cases adopting hiring credits to encourage employers to create new jobs. However, there is virtually no evidence on the effects of these kinds of counter-recessionary hiring credits - the only evidence coming from much earlier studies of the New Jobs Tax Credit from the 1970s. This paper provides evidence on the effect on job growth of hiring credits adopted during the Great Recession. For many of the types of hiring credits we examine we do not find positive effects on job growth. However, some specific types of hiring credits - including those targeting the unemployed and those that allow states to recapture credits when job creation goals are not met - appear to have succeeded in boosting job growth. At the same time, some credits appear to generate hiring without increasing employment or to generate much more hiring than net employment growth, consistent with these credits leading to churning of employees that raises the costs of producing jobs via hiring credits.
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Proprietorship and unemployment in the United States
Stephan Gohmann & Jose Fernandez
Journal of Business Venturing, forthcoming
Abstract:
Unemployment and proprietorship can be related in several ways. As unemployment increases, individuals with fewer job alternatives may choose to start their own business resulting in an increase in proprietorship. Alternatively, if an increase in unemployment is the result of a depressed economy, higher unemployment may lead to less demand for the products and services of proprietors, thus reducing proprietorship. Finally, greater proprietorship may lead to future increases in employment as these businesses grow. This can potentially reduce unemployment in the long run. We apply a panel vector autoregressive model to unemployment and proprietorship data from the U.S. states for the years 1976 to 2009 to examine if these effects are apparent in the data. We find that unemployment Granger causes proprietorship, but proprietorship does not Granger cause unemployment.
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The Growth of Low Skill Service Jobs and the Polarization of the U.S. Labor Market
David Autor & David Dorn
American Economic Review, forthcoming
Abstract:
We offer an integrated explanation and empirical analysis of the polarization of U.S. employment and wages between 1980 and 2005, and the concurrent growth of low skill service occupations. We attribute polarization to the interaction between consumer preferences, which favor variety over specialization, and the falling cost of automating routine, codifiable job tasks. Applying a spatial equilibrium model, we derive, test, and confirm four implications of this hypothesis. Local labor markets that were specialized in routine activities differentially adopted information technology, reallocated low skill labor into service occupations (employment polarization), experienced earnings growth at the tails of the distribution (wage polarization), and received inflows of skilled labor.
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The Ins and Outs of Forecasting Unemployment: Using Labor Force Flows to Forecast the Labor Market
Regis Barnichon & Christopher Nekarda
Brookings Papers on Economic Activity, Fall 2012, Pages 83-131
Abstract:
This paper presents a forecasting model of unemployment based on labor force flows data that, in real time, dramatically outperforms the Survey of Professional Forecasters, historical forecasts from the Federal Reserve Board's Greenbook, and basic time-series models. Our model's forecast has a root-mean-squared error about 30 percent below that of the next-best forecast in the near term and performs especially well surrounding large recessions and cyclical turning points. Further, because our model uses information on labor force flows that is likely not incorporated by other forecasts, a combined forecast including our model's forecast and the SPF forecast yields an improvement over the latter alone of about 35 percent for current-quarter forecasts, and 15 percent for next-quarter forecasts, as well as improvements at longer horizons.
Tuesday, April 16, 2013
May it please the court
Do Lawyers Really Believe Their Own Hype, and Should They? A Natural Experiment
Zev Eigen & Yair Listokin
Journal of Legal Studies, June 2012, Pages 239-267
Abstract:
Research suggests that attorneys are too confident in the merits of their clients' cases. But attorneys often self-select (1) the area of law in which they practice, (2) the side on which to practice within that area, (3) law firms with whom they practice, and (4) the clients they represent. We exploit a natural experiment involving participants in moot court competitions at four U.S. law schools over 2 years to explore whether, after stripping away these selection biases through random assignment to the role of petitioner or respondent, legal advocates are still overconfident in their clients' claims. We find that, following participation in moot court contests, students overwhelmingly perceive that the legal merits favor the side that they were randomly assigned to represent. We also find that overconfidence is associated with poorer performance in advocacy as measured by legal writing instructors.
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Symbol and Substance: Effects of California's Three Strikes Law on Felony Sentencing
John Sutton
Law & Society Review, March 2013, Pages 37-72
Abstract:
California's "three strikes and you're out" law is the most notorious example of the wave of mandatory sentencing policies that many states enacted beginning in the late 1970s. While advocates and critics predicted the law would have profound effects on aggregate punishment trends and individual case outcomes, Feeley and Kamin's analysis of previous sentencing reforms suggested the law's impact would be mainly symbolic because local officials would ignore, subvert, or nullify its major provisions. While aggregate analyses have tended to confirm this argument, so far there has been no systematic test of the law's effect on individual cases. This analysis uses multilevel models applied to case-level data from 12 urban California counties to test hypotheses about shifts in average punitiveness, the relative influence of legal and extralegal factors on sentencing, and the uncertainty of sentencing outcomes. Results mostly support Feeley and Kamin's symbolic interpretation, but also reveal important substantive impacts: since Three Strikes, sentences have become harsher, particularly in politically conservative counties, and black felons receive longer prison sentences.
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Hemant Sharma & Colin Glennon
Politics & Policy, April 2013, Pages 267-297
Abstract:
The desirability of complete judicial independence has been debated in several recent works. At issue is whether democratic theory is compatible with policy making by the unelected U.S. Supreme Court justices, particularly as their service becomes further removed from the time when elected officials played a role in their appointment. We examine the relationship between appointing presidents and Supreme Court justices. Relying on ideal points that place all actors in the same scale, our regression models show that a justice will drift from the ideology of an appointing president with each additional term served, even after controlling for ideological shifts in political climate. The beginning of the eleventh term is when ideological drift becomes significant. The connection between justices and democratically elected officials begins to wane after this point in a justice's tenure - a finding that is likely to be germane for proponents of term limits for Supreme Court justices.
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Do Judges Vary in Their Treatment of Race?
David Abrams, Marianne Bertrand & Sendhil Mullainathan
Journal of Legal Studies, June 2012, Pages 347-383
Abstract:
Are minorities treated differently by the legal system? Systematic racial differences in case characteristics, many unobservable, make this a difficult question to answer directly. In this paper, we estimate whether judges differ from each other in how they sentence minorities, avoiding potential bias from unobservable case characteristics by exploiting the random assignment of cases to judges. We measure the between-judge variation in the difference in incarceration rates and sentence lengths between African American and white defendants. We perform a Monte Carlo simulation in order to explicitly construct the appropriate counterfactual, in which race does not influence judicial sentencing. In our data set, which includes felony cases from Cook County, Illinois, we find statistically significant between-judge variation in incarceration rates, although not in sentence lengths.
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The Effects of Legal and Extralegal Factors on Detention Decisions in US District Courts
Angela Reitler, Christopher Sullivan & James Frank
Justice Quarterly, March/April 2013, Pages 340-368
Abstract:
The Bail Reform Act of 1984 changed the law dictating release and detention decisions in federal court. Since its passage, few studies have examined judicial decision-making in this context. Legal research enables us to account for the structure and interpretation of federal detention laws and to analyze previously neglected measures of legal factors in our analyses. We use US Sentencing Commission data on a sample of defendants who were sentenced in 2007 (N = 31,043). We find that legal factors - particularly length of criminal history, having committed a violent or otherwise serious offense, and having committed the offense while under supervision of the criminal justice system - have the strongest relationships with the presentence detention outcome. A defendant's age, race, and ethnicity have weaker relationships with detention. When we compare defendants who are similarly situated with respect to legal factors, the probability of detention is similar regardless of age, race, and ethnicity.
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Kevin Beaver et al.
Personality and Individual Differences, July 2013, Pages 29-34
Abstract:
One of the most consistent findings in the criminological literature is that African American males are arrested, convicted, and incarcerated at rates that far exceed those of any other racial or ethnic group. This racial disparity is frequently interpreted as evidence that the criminal justice system is racist and biased against African American males. Much of the existing literature purportedly supporting this interpretation, however, fails to estimate properly specified statistical models that control for a range of individual-level factors. The current study was designed to address this shortcoming by analyzing a sample of African American and White males drawn from the National Longitudinal Study of Adolescent Health (Add Health). Analysis of these data revealed that African American males are significantly more likely to be arrested and incarcerated when compared to White males. This racial disparity, however, was completely accounted for after including covariates for self-reported lifetime violence and IQ. Implications of this study are discussed and avenues for future research are offered.
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Rob Tillyer & Robin Engel
Crime & Delinquency, April 2013, Pages 369-395
Abstract:
Recent research has demonstrated that minority drivers receive disparate traffic stop outcomes compared with similarly situated White drivers. This research, however, is often not grounded within a theoretical framework and fails to examine specific combinations of driver demographics. This study addresses those shortcomings by examining research questions based on the social conditioning model and investigating the relationship between specific combinations of drivers' race/ethnicity, gender, and age, and traffic stop outcomes. Using alternative measures of stop outcomes and robust official traffic stop data collected from a state law enforcement agency, the results demonstrate that warnings and citations, but not arrests, are differentially issued to young, Black male drivers. The findings also confirm the influence of legal factors on police decision making during traffic stops. Research and policy implications are discussed.
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Sentencing Native Americans in US Federal Courts: An Examination of Disparity
Travis Franklin
Justice Quarterly, March/April 2013, Pages 310-339
Abstract:
Existing sentencing literature largely focuses on the study of white, African-American, and to a lesser extent, Hispanic offenders. Unfortunately, very little is known about the sentencing of Native American offenders, especially in the federal courts. To address this shortcoming, the current study employs United States Sentencing Commission data for the fiscal years 2006-2008 to examine the comparative punishment of Native Americans. Consistent with the focal concerns perspective and its reliance on perceptions of race-based threat, findings demonstrate that Native Americans are often sentenced more harshly than white, African-American, and Hispanic offenders. Moreover, race-gender-age interactions indicate that during the incarceration decision, young Native American males receive the most punitive sentences, surpassing the punishment costs associated with being a young African-American or Hispanic male. These findings highlight the importance of directing increased attention toward the sentencing of this understudied offender population.
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Implementation of Anti-Discrimination Policy: Does Judicial Selection Matter?
Timothy Besley & Abigail Payne
American Law and Economics Review, Spring 2013, Pages 212-251
Abstract:
Legislation to limit workplace discrimination is among the most common reforms in labor market policy of the past 50 years. Its effectiveness depends on enforcement of the legislation by state and federal agencies and, ultimately, the courts. This paper uses information on discrimination charges in the United States between 1973 and 2000 to analyze whether the number of charges filed is correlated with the method by which state judges are selected. We find evidence that states that appoint their judges have significantly fewer anti-discrimination charges being filed.
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A Fundamental Enforcement Cost Advantage of the Negligence Rule over Regulation
Steven Shavell
Harvard Working Paper, February 2013
Abstract:
Regulation and the negligence rule are both designed to obtain compliance with desired standards of behavior, but they differ in a primary respect: compliance with regulation is ordinarily assessed independently of the occurrence of harm, whereas compliance with the negligence rule is evaluated only if harm occurs. It is shown in a stylized model that because the use of the negligence rule is triggered by harm, the rule enjoys an intrinsic enforcement cost advantage over regulation. Moreover, this advantage suggests that the examination of behavior under the negligence rule should tend to be more detailed than under regulation (as it is).
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The Disappearance of Civil Trial in the United States
John Langbein
Yale Law Journal, December 2012, Pages 522-572
Abstract:
Since the 1930s, the proportion of civil cases concluded at trial has declined from about 20% to below 2% in the federal courts and below 1% in state courts. This Article looks to the history of the civil trial to explain why the trial endured so long and then vanished so rapidly. For the litigants, a civil procedure system serves two connected functions: investigating the facts and adjudicating the dispute. The better the system investigates and clarifies the facts, the more it promotes settlement and reduces the need to adjudicate. The Anglo-American common law for most of its history paid scant attention to the investigative function. This Article points to the role of the jury system in shaping the procedure and restricting the investigative function. Pleading was the only significant component of pretrial procedure, and the dominant function of pleading was to control the jury by narrowing to a single issue the question that the jury would be asked to decide. This primitive pretrial process left trial as the only occasion at which it was sometimes possible to investigate issues of fact. Over time, the jury-free equity courts developed techniques to enable litigants to obtain testimonial and documentary evidence in advance of adjudication. The fusion of law and equity in the Federal Rules of Civil Procedure of 1938 brought those techniques into the merged procedure, and expanded them notably. The signature reform of the Federal Rules was to shift pretrial procedure from pleading to discovery. A new system of civil procedure emerged, centered on the discovery of documents and the sworn depositions of parties and witnesses. Related innovations, the pretrial conference and summary judgment, reinforced the substitution of discovery for trial. This new procedure system has overcome the investigation deficit that so afflicted common law procedure, enabling almost all cases to be settled or dismissed without trial. Pretrial procedure has become nontrial procedure by making trial obsolete.
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Trying to Get What You Want: Heresthetical Maneuvering and U.S. Supreme Court Decision Making
Ryan Black, Rachel Schutte & Timothy Johnson
Political Research Quarterly, forthcoming
Abstract:
Riker famously theorized that political actors faced with suboptimal outcomes might be able to garner a more desirable one by adding issues to the agenda. To date, limited support for Riker's theory of heresthetics exists, primarily consisting of case studies and anecdotal evidence. We offer a systematic analysis of heresthetical maneuvers in the context of Supreme Court decision making. We argue justices who oppose a potential case outcome may add alternative issues to the record in an effort to restructure the terms of debate. Data from justices' behavior during oral argument support Riker's theory.
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The insured victim effect: When and why compensating harm decreases punishment recommendations
Philippe van de Calseyde, Gideon Keren & Marcel Zeelenberg
Judgment and Decision Making, March 2013, Pages 161-173
Abstract:
An insurance policy may not only affect the consequences for victims but also for perpetrators. In six experiments we find that people recommend milder punishments for perpetrators when the victim was insured, although people believe that a sentence should not depend on the victim's insurance status. The robustness of this effect is demonstrated by showing that recommendations can even be more lenient for crimes that are in fact more serious but in which the victim was insured. Moreover, even when harm was possible but did not materialize, people still prefer to punish crimes less severely when the (potential) victim was insured. The final two experiments suggest that the effect is associated with a change in (1) compassion for the victim and (2) perceived severity of the transgression. Implications of this phenomenon are briefly discussed.
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Speech style and occupational status affect assessments of eyewitness testimony
Sean Jules & Dawn McQuiston
Journal of Applied Social Psychology, April 2013, Pages 741-748
Abstract:
This study examined how speech style and occupational status affect mock jurors' assessments of eyewitness testimony. Mock jurors (n = 120) watched a video of a man testifying about witnessing an attempted robbery. The eyewitness exhibited either a powerless or powerful speech style and reported either a high or low (or no) status occupation during his testimony. Results indicated that high occupation status and powerful speech style led to more favorable evaluations of the eyewitness's testimony and of the case against the defendant than powerless speech style and low/no occupation status. Implications of these results on considerations of eyewitness testimony and future research are discussed.
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Nicola Persico
Journal of Legal Studies, June 2012, Pages 321-346
Abstract:
This paper develops a decision-theoretic model of evidence production in the context of a discrimination trial. Producing evidence is assumed to be costly, and the cost can vary depending on what type of defendant behavior (and plaintiff characteristics) the evidence bears upon. The goal of the trial is to uncover a possible behavioral bias in the defendant (intent to discriminate). I then ask how a social planner would structure the production of evidence in a trial in order to best achieve this objective, taking into account the cost of evidence production. I show that it is sometimes efficient to sequence the production of different kinds of evidence (burden shifting) or even to allow a decision based on limited evidence (for example, disparate impact alone, as a proxy for intent to discriminate). A key variable is the availability of evidence concerning the productivity of the plaintiff.
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National Policy Preferences and Judicial Review of State Statutes at the United States Supreme Court
Stefanie Lindquist & Pamela Corley
Publius, Spring 2013, Pages 151-178
Abstract:
This article explores the determinants of U.S. Supreme Court justices' voting behavior in cases involving constitutional challenges to state statutes, with a particular focus on the degree to which majoritarian influences - as reflected in state participation and congressional preferences - affect the justices' votes. We find that the scope of the Court's decision - in terms of its impact on similar state laws and the expressed interest of states as amicus - strongly affects the justices' willingness to vote to invalidate a state statute. Moreover, at least in the Burger Court, the justices were constrained by congressional preferences over the ideological direction of the constitutional challenge. Justices on the Rehnquist Court, however, appear to have been more impervious to congressional preferences when evaluating the constitutionality of state legislation.
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Can Drug Courts Help to Reduce Prison and Jail Populations?
Eric Sevigny, Harold Pollack & Peter Reuter
ANNALS of the American Academy of Political and Social Science, May 2013, Pages 190-212
Abstract:
Drug courts have been widely praised as an important tool for reducing prison and jail populations by diverting drug-involved offenders into treatment rather than incarceration. Yet only a small share of offenders presenting with drug abuse or dependence are processed in drug courts. This study uses inmate self-report surveys from 2002 and 2004 to examine characteristics of the prison and jail populations in the United States and assess why so many drug-involved offenders are incarcerated. Our analysis shows that four factors have prevented drug courts from substantially lowering the flow into prisons and jails. In descending order of importance, these are: drug courts' tight eligibility requirements, specific sentencing requirements, legal consequences of program noncompliance, and constraints in drug court capacity and funding. Drug courts will only be able to help lower prison and jail populations if substantial changes are made in eligibility and sentencing rules.
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The Role of Medicolegal Systems in Producing Geographic Variation in Suicide Rates
Joshua Klugman, Gretchen Condran & Matt Wray
Social Science Quarterly, forthcoming
Objectives: In this analysis, we ask whether there is systematic variation in the reporting of suicide by medicolegal system and if so whether this biases estimated effects of social correlates on suicide.
Methods: With cause of death records (1999-2002) and 2000 Census data, we use negative binomial regression to analyze the effects of medicolegal system on suicide and nonsuicide mortality aggregated at county of occurrence.
Results: We find that elected coroners have slightly lower official suicide rates than medical examiners (MEs; all of whom are appointed) and appointed coroners. In addition, we find that omitting medicolegal system does not bias estimates of the social determinants of suicide.
Conclusion: Contrary to arguments that MEs' greater scientific training makes them more likely to underreport suicides, we conclude that appointed death investigators (MEs and appointed coroners) underreport suicide to a lesser degree than elected coroners, who are subject to greater public pressures that result in the misclassification of suicides.
Monday, April 15, 2013
Downsizing
Regulating the Way to Obesity: Unintended Consequences of Limiting Sugary Drink Sizes
Brent Wilson, Stephanie Stolarz-Fantino & Edmund Fantino
PLoS ONE, April 2013
Objectives: We examined whether a sugary drink limit would still be effective if larger-sized drinks were converted into bundles of smaller-sized drinks.
Methods: In a behavioral simulation, participants were offered varying food and drink menus. One menu offered 16 oz, 24 oz, or 32 oz drinks for sale. A second menu offered 16 oz drinks, a bundle of two 12 oz drinks, or a bundle of two 16 oz drinks. A third menu offered only 16 oz drinks for sale. The method involved repeated elicitation of choices, and the instructions did not mention a limit on drink size.
Results: Participants bought significantly more ounces of soda with bundles than with varying-sized drinks. Total business revenue was also higher when bundles rather than only small-sized drinks were sold.
Conclusions: Our research suggests that businesses have a strong incentive to offer bundles of soda when drink size is limited. Restricting larger-sized drinks may have the unintended consequence of increasing soda consumption rather than decreasing it.
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Ecological Contingencies in Women's Calorie Regulation Psychology: A Life History Approach
Sarah Hill et al.
Journal of Experimental Social Psychology, forthcoming
Abstract:
We used insights from life history theory and the critical fat hypothesis to explore how environmental harshness influences women's food and weight regulation psychology. As predicted by our theoretical model, women who grew up in poorer, more unpredictable environments responded to harshness cues in their adult environments by exhibiting a greater desire for food (Studies 1 and 2) and a diminished concern with calorie restriction and weight loss (Study 3). In sharp contrast, women who grew up in more predictable, wealthier environments responded to these cues by exhibiting a diminished desire for food and increased concern with calorie restriction and weight loss. This research provides novel insights into the role that local environmental factors play in women's food and weight regulation psychology.
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Weightism, Racism, Classism, and Sexism: Shared Forms of Harassment in Adolescents
Michaela Bucchianeri et al.
Journal of Adolescent Health, forthcoming
Purpose: To document the prevalence of harassment on the basis of weight, race/ethnicity, and socioeconomic status, as well as sexual harassment, among a diverse population of adolescents. Specifically, this study examined rates of each type of harassment reported across groups within the corresponding sociodemographic category (e.g., racial/ethnic category differences in prevalence of racial harassment), and also explored patterns of "cross-harassment" (i.e., differences in prevalence of each harassment type across all other sociodemographic characteristics).
Methods: We used data from Project Eating and Activity in Teens 2010 for the study. The sample was composed of 2,793 adolescents (53% female; 81% nonwhite). We conducted regression analyses to yield prevalence estimates of each type of harassment in each demographic and body mass index category.
Results: Weight- and race-based harassment (35.3% and 35.2%, respectively) was most prevalent, followed by sexual harassment (25.0%) and socioeconomic status-based harassment (16.1%). Overweight and obese adolescents reported disproportionately higher rates of all forms of harassment than did normal-weight and underweight adolescents. In addition, Asian and mixed-/other race adolescents were more vulnerable to harassment overall compared with those from other racial/ethnic groups.
Conclusions: Harassment experiences are prevalent among adolescent boys and girls. Differential rates of each type of harassment are reported across groups within the corresponding sociodemographic category, but a pattern of cross-harassment also is evident, such that differences in prevalence of each type of harassment emerge across a variety of sociodemographic characteristics. Adolescents from various intersecting sociodemographic and weight-status groups are particularly vulnerable to certain types of harassment.
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Andreana Kenrick, Jenessa Shapiro & Steven Neuberg
Social Psychological and Personality Science, forthcoming
Abstract:
This study examined whether and under what conditions parents might stereotype their own heavyweight children. Parents completed a survey assessing their beliefs about their 9- to 11-year-old children. Parents were also assessed on factors previously demonstrated to moderate people's reactions to heavyweight strangers, including Protestant work ethic (PWE) and personal vulnerability to disease. Consistent with findings on how people view heavyweight strangers, parents who endorsed the PWE or had enhanced disease concerns attributed negative fat stereotypes (e.g., laziness, lacking self-control) to their heavyweight children. Although parental identification did not moderate stereotyping of one's overweight children, those individuals who highly identified with their role as parents spent more time with their heavier-weight children, potentially reflecting a compensatory pattern of behaviors. That even parents negatively stereotype their young heavyweight children reveals the long reach of the anti-fat psychology and suggests that efforts to mitigate the application of fat stereotypes may be particularly difficult.
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Sarah Cohen et al.
PLoS ONE, April 2013
Abstract:
Increased sedentary behavior and lack of physical activity are associated with increased risk for many chronic diseases. Differences in leisure-time physical activity between African American and white adults have been suggested to partially explain racial disparities in chronic disease outcomes, but expanding the definition of physical activity to include household and occupational activities may reduce or even eliminate racial differences in total physical activity. The objective of this study was to describe patterns of active and sedentary behaviors in black and white adults and to examine these behaviors across demographic measures. Sedentary and physically active behaviors were obtained from a validated physical activity questionnaire in 23,021 black men, 9,899 white men, 32,214 black women, and 15,425 white women (age 40-79) at enrollment into the Southern Community Cohort Study. Descriptive statistics for sedentary time; light, moderate, and vigorous household/occupational activity; sports/exercise; total activity; and meeting current physical activity recommendations via sports/exercise were examined for each race-sex group. Adjusted means were calculated using multiple linear regression models across demographic measures. Study participants spent approximately 60% of waking time in sedentary behaviors. Blacks reported more television viewing time than whites (45 minutes for females, 15 minutes for males), but when sitting time was expressed as a proportion of overall awake time, minimal racial differences were found. Patterns of light, moderate, and vigorous household/occupational activity were similar in all race/sex groups. 2008 Physical Activity Guidelines for Americans were followed by 16% of women and 25% of men independent of race. Overall, black and white men and women in this study spent the majority of their daily time in sedentary behaviors and less than one-fourth followed current guidelines for physical activity. These results indicate that public health campaigns should focus on both reducing sedentary behavior and increasing physical activity in all adult US populations.
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Impact of insufficient sleep on total daily energy expenditure, food intake, and weight gain
Rachel Markwald et al.
Proceedings of the National Academy of Sciences, 2 April 2013, Pages 5695-5700
Abstract:
Insufficient sleep is associated with obesity, yet little is known about how repeated nights of insufficient sleep influence energy expenditure and balance. We studied 16 adults in a 14- to 15-d-long inpatient study and quantified effects of 5 d of insufficient sleep, equivalent to a work week, on energy expenditure and energy intake compared with adequate sleep. We found that insufficient sleep increased total daily energy expenditure by ∼5%; however, energy intake - especially at night after dinner - was in excess of energy needed to maintain energy balance. Insufficient sleep led to 0.82 ± 0.47 kg (±SD) weight gain despite changes in hunger and satiety hormones ghrelin and leptin, and peptide YY, which signaled excess energy stores. Insufficient sleep delayed circadian melatonin phase and also led to an earlier circadian phase of wake time. Sex differences showed women, not men, maintained weight during adequate sleep, whereas insufficient sleep reduced dietary restraint and led to weight gain in women. Our findings suggest that increased food intake during insufficient sleep is a physiological adaptation to provide energy needed to sustain additional wakefulness; yet when food is easily accessible, intake surpasses that needed. We also found that transitioning from an insufficient to adequate/recovery sleep schedule decreased energy intake, especially of fats and carbohydrates, and led to -0.03 ± 0.50 kg weight loss. These findings provide evidence that sleep plays a key role in energy metabolism. Importantly, they demonstrate physiological and behavioral mechanisms by which insufficient sleep may contribute to overweight and obesity.
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Characteristics of Screen Media Use Associated With Higher BMI in Young Adolescents
David Bickham et al.
Pediatrics, forthcoming
Objectives: This study investigates how characteristics of young adolescents' screen media use are associated with their BMI. By examining relationships between BMI and both time spent using each of 3 screen media and level of attention allocated to use, we sought to contribute to the understanding of mechanisms linking media use and obesity.
Methods: We measured heights and weights of 91 13- to 15-year-olds and calculated their BMIs. Over 1 week, participants completed a weekday and a Saturday 24-hour time-use diary in which they reported the amount of time they spent using TV, computers, and video games. Participants carried handheld computers and responded to 4 to 7 random signals per day by completing onscreen questionnaires reporting activities to which they were paying primary, secondary, and tertiary attention.
Results: Higher proportions of primary attention to TV were positively associated with higher BMI. The difference between 25th and 75th percentiles of attention to TV corresponded to an estimated +2.4 BMI points. Time spent watching television was unrelated to BMI. Neither duration of use nor extent of attention paid to video games or computers was associated with BMI.
Conclusions: These findings support the notion that attention to TV is a key element of the increased obesity risk associated with TV viewing. Mechanisms may include the influence of TV commercials on preferences for energy-dense, nutritionally questionable foods and/or eating while distracted by TV. Interventions that interrupt these processes may be effective in decreasing obesity among screen media users.
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Heather Leidy et al.
American Journal of Clinical Nutrition, April 2013, Pages 677-688
Background: Breakfast skipping is a common dietary habit practiced among adolescents and is strongly associated with obesity.
Objective: The objective was to examine whether a high-protein (HP) compared with a normal-protein (NP) breakfast leads to daily improvements in appetite, satiety, food motivation and reward, and evening snacking in overweight or obese breakfast-skipping girls.
Design: A randomized crossover design was incorporated in which 20 girls [mean ± SEM age: 19 ± 1 y; body mass index (in kg/m2): 28.6 ± 0.7] consumed 350-kcal NP (13 g protein) cereal-based breakfasts, consumed 350-kcal HP egg- and beef-rich (35 g protein) breakfasts, or continued breakfast skipping (BS) for 6 d. On day 7, a 10-h testing day was completed that included appetite and satiety questionnaires, blood sampling, predinner food cue-stimulated functional magnetic resonance imaging brain scans, ad libitum dinner, and evening snacking.
Results: The consumption of breakfast reduced daily hunger compared with BS with no differences between meals. Breakfast increased daily fullness compared with BS, with the HP breakfast eliciting greater increases than did the NP breakfast. HP, but not NP, reduced daily ghrelin and increased daily peptide YY concentrations compared with BS. Both meals reduced predinner amygdala, hippocampal, and midfrontal corticolimbic activation compared with BS. HP led to additional reductions in hippocampal and parahippocampal activation compared with NP. HP, but not NP, reduced evening snacking of high-fat foods compared with BS.
Conclusions: Breakfast led to beneficial alterations in the appetitive, hormonal, and neural signals that control food intake regulation. Only the HP breakfast led to further alterations in these signals and reduced evening snacking compared with BS, although no differences in daily energy intake were observed. These data suggest that the addition of breakfast, particularly one rich in protein, might be a useful strategy to improve satiety, reduce food motivation and reward, and improve diet quality in overweight or obese teenage girls.
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Does Weight Affect Children's Test Scores and Teacher Assessments Differently?
Madeline Zavodny
Economics of Education Review, June 2013, Pages 135-145
Abstract:
The prevalence of childhood overweight and obesity increased dramatically in the United States during the past three decades. This increase has adverse public health implications, but its implication for children's academic outcomes is less clear. This paper uses data from five waves of the Early Childhood Longitudinal Study-Kindergarten to examine how children's weight is related to their scores on standardized tests and to their teachers' assessments of their academic ability. The results indicate that children's weight is more negatively related to teacher assessments of their academic performance than to test scores.
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Sleep Duration and Adolescent Obesity
Jonathan Mitchell et al.
Pediatrics, forthcoming
Objectives: Short sleep has been associated with adolescent obesity. Most studies used a cross-sectional design and modeled BMI categories. We sought to determine if sleep duration was associated with BMI distribution changes from age 14 to 18.
Methods: Adolescents were recruited from suburban high schools in Philadelphia when entering ninth grade (n = 1390) and were followed-up every 6 months through 12th grade. Height and weight were self-reported, and BMIs were calculated (kg/m2). Hours of sleep were self-reported. Quantile regression was used to model the 10th, 25th, 50th, 75th, and 90th BMI percentiles as dependent variables; study wave and sleep were the main predictors.
Results: BMI increased from age 14 to 18, with the largest increase observed at the 90th BMI percentile. Each additional hour of sleep was associated with decreases in BMI at the 10th (-0.04; 95% confidence interval [CI]: -0.11, 0.03), 25th (-0.12; 95% CI: -0.20, -0.04), 50th (-0.15; 95% CI: -0.24, -0.06), 75th (-0.25; 95% CI: -0.38, -0.12), and 90th (-0.27; 95% CI: -0.45, -0.09) BMI percentiles. The strength of the association was stronger at the upper tail of the BMI distribution. Increasing sleep from 7.5 to 10.0 hours per day at age 18 predicted a reduction in the proportion of adolescents >25 kg/m2 by 4%.
Conclusions: More sleep was associated with nonuniform changes in BMI distribution from age 14 to 18. Increasing sleep among adolescents, especially those in the upper half of the BMI distribution, may help prevent overweight and obesity.
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A Randomized Controlled Trial of an Appearance-Based Dietary Intervention
Ross Whitehead, Gözde Ozakinci & David Perrett
Health Psychology, forthcoming
Objective: Inadequate fruit and vegetable consumption precipitates preventable morbidity and mortality. The efficacy of an appearance-based dietary intervention was investigated, which illustrates the beneficial effect that fruit and vegetable consumption has on skin appearance.
Methods: Participants were randomly allocated to three groups receiving information-only or a generic or own-face appearance-based intervention. Diet was recorded at baseline and 10 weekly follow-ups. Participants in the generic and own-face intervention groups witnessed on-screen stimuli and received printed photographic materials to illustrate the beneficial effect of fruit and vegetable consumption on skin color.
Results: Controlling for baseline diet, a significant effect of intervention group was found on self-reported fruit and vegetable intake among 46 completers who were free of medical and personal reasons preventing diet change. The own-face appearance-based intervention group reported a significant, sustained improvement in fruit and vegetable consumption whereas the information-only and generic appearance-based intervention groups reported no significant dietary changes.
Conclusions: Seeing the potential benefits of fruit and vegetable consumption on own skin color may motivate dietary improvement.
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Sit Big to Eat Big: The Interaction of Body Posture and Body Concern on Restrained Eating
Jill Allen, Sarah Gervais & Jessi Smith
Psychology of Women Quarterly, forthcoming
Abstract:
Body image concern has long been linked with unhealthy restrained eating patterns among women, yet scant research has examined factors to disrupt this process. At the same time, feminine stereotypes prescribe that women should be small, restrict their movements, speak softly, and limit their food intake (e.g., through dieting). Here, we examined whether women's postural constriction or expansion moderated the relation between body shape concern and restrained eating, predicting that expansive postures would interrupt this robust relation. As a secondary aim, we investigated whether women spontaneously adopted constrictive postures and to what extent postures contributed to restrained eating under baseline conditions. Specifically, women's postural position (constricted, expanded, or baseline posture) was manipulated and restrained eating was measured. Results showed that at high levels of body shape concern, women sitting in expansive postures restrained their eating less compared to women in constrictive postures. Further, spontaneously expansive (vs. spontaneously constrictive) postures were associated with less restrained eating among women. Thus, postural expansion attenuated the link between body shape concern and restrained eating whereas postural constriction exacerbated the link. Implications for gender performativity and possible interventions for restrained eating are discussed.
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Plate Size and Children's Appetite: Effects of Larger Dishware on Self-Served Portions and Intake
Katherine DiSantis et al.
Pediatrics, forthcoming
Objectives: Dishware size is thought to influence eating behaviors, but effects on children's self-served portion sizes and intakes have not been studied. We aimed to evaluate whether larger dishware increased children's self-served portion sizes and intake during meals.
Methods: A within-subjects experimental design was used to test the effects of dishware size (ie, plates and bowls) on children's self-served portion sizes and intakes in a naturalistic setting. Subjects were predominantly African American elementary school-aged children (n = 42) observed on repeated occasions during school lunch. Children served themselves an entree and side dishes using either child- or adult-size dishware, which represented a 100% increase in the surface area of plates and volume of bowls across conditions. Condition order was randomly assigned and counterbalanced across 2 first-grade classrooms. Entrées of amorphous and unit form were evaluated on separate days. Fruit and vegetable side dishes were evaluated at each meal. Fixed portions of milk and bread were provided at each meal.
Results: Children served more energy (mean = 90.1 kcal, SE = 29.4 kcal) when using adult-size dishware. Adult-size dishware promoted energy intake indirectly, where every additional calorie served resulted in a 0.43-kcal increase in total energy intakes at lunch (t = 7.72, P = .001).
Conclusions: Children served themselves more with larger plates and bowls and consumed nearly 50% of the calories that they served. This provides new evidence that children's self-served portion sizes are influenced by size-related facets of their eating environments, which, in turn, may influence children's energy intake.
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Health on Impulse: When Low Self-Control Promotes Healthy Food Choices
Stefanie Salmon et al.
Health Psychology, forthcoming
Objective: Food choices are often made mindlessly, when individuals are not able or willing to exert self-control. Under low self-control, individuals have difficulties to resist palatable but unhealthy food products. In contrast to previous research aiming to foster healthy choices by promoting high self-control, this study exploits situations of low self-control, by strategically using the tendency under these conditions to rely on heuristics (simple decision rules) as quick guides to action. More specifically, the authors associated healthy food products with the social proof heuristic (i.e., normative cues that convey majority endorsement for those products).
Method: One hundred seventy-seven students (119 men), with an average age of 20.47 years (SD = 2.25) participated in the experiment. This study used a 2 (low vs. high self-control) × 2 (social proof vs. no heuristic) × 2 (trade-off vs. control choice) design, with the latter as within-subjects factor. The dependent variable was the number of healthy food choices in a food-choice task.
Results: In line with previous studies, people made fewer healthy food choices under low self-control. However, this negative effect of low self-control on food choice was reversed when the healthy option was associated with the social proof heuristic. In that case, people made more healthy choices under conditions of low self-control.
Conclusion: Low self-control may be even more beneficial for healthy food choices than high self-control in the presence of a heuristic. Exploiting situations of low self-control is a new and promising method to promote health on impulse.
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M.S. Tryon, Rashel DeCant & K.D. Laugero
Physiology & Behavior, forthcoming
Abstract:
Stress has been tied to changes in eating behavior and food choice. Previous studies in rodents have shown that chronic stress increases palatable food intake which, in turn, increases mesenteric fat and inhibits acute stress-induced hypothalamic-pituitary-adrenal (HPA) axis activity. The effect of chronic stress on eating behavior in humans is less understood, but it may be linked to HPA responsivity. The purpose of this study was to investigate the influence of chronic social stress and acute stress reactivity on food choice and food intake. Forty-one women (BMI = 25.9 ± 5.1 kg/m2, age range = 41 to 52 years) were subjected to the Trier Social Stress Task or a control task (nature movie) to examine HPA responses to an acute laboratory stressor and then invited to eat from a buffet containing low- and high- calorie "comfort" snacks. Women were also categorized as high chronic stress or low chronic stress based on Wheaton Social Stress Index scores. Women reporting higher chronic stress and exhibiting low cortisol reactivity to the acute stress task consumed significantly more calories from chocolate cake on both stress and control visits. Chronic stress in the low cortisol reactor group was also positively related to total fat mass, regional fat percentage, and stress-induced negative mood. Further, women reporting high chronic stress consumed significantly less vegetables, but only in those aged 45 years and older. Chronic stress in women within the higher age category was positively related to total calories consumed at the buffet, stress-induced negative mood and food craving. Our results suggest an increased risk for stress eating in persons with a specific chronic stress signature and imply that a habit of comfort food may link chronic social stress and acute stress-induced cortisol hyporesponsiveness.
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Weight perceptions, weight control and income: An analysis using British Data
David Johnston & Grace Lordan
Economics & Human Biology, forthcoming
Abstract:
The aim of this paper is to better understand one of the mechanisms underlying the income-obesity relationship so that effective policy interventions can be developed. Our approach involves analysing data on approximately 9,000 overweight British adults from between 1997 and 2002. We estimate the effect of income on the probability that an overweight individual correctly recognises their overweight status and the effect of income on the probability that an overweight individual attempts to lose weight. The results suggest that high income individuals are more likely to recognise their unhealthy weight status, and conditional on this correct weight perception, more likely to attempt weight loss. For example, it is estimated that overweight high income males are 15 percentage-points more likely to recognize their overweight status than overweight low income males, and overweight high income males are 10 percentage-points more likely to be trying to lose weight. An implication of these results is that more public education on what constitutes overweight and the dangers associated with being overweight is needed, especially in low income neighbourhoods.
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Body mass index and neurocognitive functioning across the adult lifespan
Kelly Stanek et al.
Neuropsychology, March 2013, Pages 141-151
Objective: Cognitive dysfunction and structural brain abnormalities have been observed in obese versus lean individuals, but with variability across age and weight groups. The current study was designed to clarify the cognitive profile of obesity by examining performance across multiple cognitive domains in adults with wide-ranging age and weight status.
Method: Participants (N = 732; 61% women; ages 18-88; BMI range 19-75) underwent assessment of cognitive functioning and relevant medical/demographic covariates. Neuropsychological tests were grouped by cognitive domain (via confirmatory factor analysis), and standardized scores were averaged into composite variables.
Results: Hierarchical linear regression analyses revealed main effects for BMI on motor (ΔR2 = .02, β = -.15) and attention/processing speed (ΔR2 = .01, β = -.07), whereas a significant interaction between BMI and age was observed (ΔR2 = .01, β = -.08) for predicting executive functioning (p < .05). BMI was not independently associated with memory or language functioning and no interaction effects were observed for these variables. Although BMI was not independently related to executive dysfunction, a significant age × BMI interaction suggests that obesity-related executive deficits may increase with age.
Conclusions: Overall, these findings may support an independent association between obesity and a frontal-subcortical pathology, though prospective studies are needed to further clarify this possibility.
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Perceived and actual social discrimination: The case of overweight and social inclusion
Freda-Marie Hartung & Britta Renner
Frontiers in Psychology, April 2013
Abstract:
The present study examined the correspondence between perceived and actual social discrimination of overweight people. In total, 77 first-year students provided self-ratings about their height, weight, and perceived social inclusion. To capture actual social inclusion, each participant nominated those fellow students (a) she/he likes and dislikes and (b) about whom she/he is likely to hear social news. Students with lower Body Mass Index (BMI) felt socially included, irrespective of their actual social inclusion. In contrast, students with higher BMI felt socially included depending on the degree of their actual social inclusion. Specifically, their felt social inclusion accurately reflected whether they were actually liked/disliked, but only when they were part of social news. When not part of social news, they also showed insensitivity to their actual social inclusion status. Thus, students with a lower BMI tended to be insensitive, while students with a higher BMI showed a differential sensitivity to actual social discrimination.
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Ming Wen & Thomas Maloney
Economics & Human Biology, forthcoming
Abstract:
We build on recent work examining the BMI patterns of immigrants in the US by distinguishing between legal and undocumented immigrants. We find that undocumented women have relative odds of obesity that are about 10 percentage points higher than for legal immigrant women, and their relative odds of being overweight are about 40 percentage points higher. We also find that the odds of obesity and overweight status vary less across neighborhoods for undocumented women than for legal immigrant women. These patterns are not found among immigrant men: undocumented men have lower rates of obesity (by about 6 percentage points in terms of relative odds) and overweight (by about 12 percentage points) than do legal immigrant men, and there is little variation in the impact of neighborhood context across groups of men. We interpret these findings in terms of processes of acculturation among immigrant men and women.
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John Cawley, Rosemary Avery & Matthew Eisenberg
NBER Working Paper, March 2013
Abstract:
This paper is the first to estimate the impact of exposure to deceptive advertising on consumption of the advertised product and its substitutes. We study the market for over-the-counter (OTC) weight-loss products, a market in which deceptive advertising is rampant and products are generally ineffective with potentially serious side effects. We control for the targeting of ads using indicator variables for each unique magazine read and television show watched. Our estimates indicate that exposure to deceptive advertising is associated with a lower probability that women, and a higher probability that men, consume OTC weight loss products. We find evidence of spillovers; exposure to deceptive print ads is associated with a higher probability of dieting and exercising for both men and women. We also find evidence that better-educated individuals are more sophisticated consumers of advertising and use it to make more health-promoting decisions.
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A.M. Adachi-Mejia et al.
Public Health, forthcoming
Objectives: The 2010 Dietary Guidelines for Americans include reducing consumption of sugar-sweetened beverages. Among the many possible routes of access for youth, school vending machines provide ready availability of sugar-sweetened beverages. The purpose of this study was to determine variation in high school student access to sugar-sweetened beverages through vending machines by geographic location - urban, town or rural - and to offer an approach for analysing school vending machine content.
Study design: Cross-sectional observational study.
Methods: Between October 2007 and May 2008, trained coders recorded beverage vending machine content and machine-front advertising in 113 machines across 26 schools in New Hampshire and Vermont, USA.
Results: Compared with town schools, urban schools were significantly less likely to offer sugar-sweetened beverages (P = 0.002). Rural schools also offered more sugar-sweetened beverages than urban schools, but this difference was not significant. Advertisements for sugar-sweetened beverages were highly prevalent in town schools.
Conclusions: High school students have ready access to sugar-sweetened beverages through their school vending machines. Town schools offer the highest risk of exposure; school vending machines located in towns offer up to twice as much access to sugar-sweetened beverages in both content and advertising compared with urban locations. Variation by geographic region suggests that healthier environments are possible and some schools can lead as inspirational role models.
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Two Functional Serotonin Polymorphisms Moderate the Effect of Food Reinforcement on BMI
Katelyn Carr et al.
Behavioral Neuroscience, forthcoming
Abstract:
Food reinforcement, or the motivation to eat, has been associated with increased energy intake, greater body weight, and prospective weight gain. Much of the previous research on the reinforcing value of food has focused on the role of dopamine, but it may be worthwhile to examine genetic polymorphisms in the serotonin and opioid systems as these neurotransmitters have been shown to be related to reinforcement processes and to influence energy intake. We examined the relationship among 44 candidate genetic polymorphisms in the dopamine, serotonin, and opioid systems, as well as food reinforcement and body mass index (BMI) in a sample of 245 individuals. Polymorphisms in the monoamine oxidase A (MAOA-LPR) and serotonin receptor 2A genes (rs6314) moderated the effect of food reinforcement on BMI, accounting for an additional 5-10% variance and revealed a potential role of the single nucleotide polymorphism, rs6314, in the serotonin 2A receptor as a differential susceptibility factor for obesity. Differential susceptibility describes a factor that can confer either risk or protection depending on a second variable, such that rs6314 is predictive of both high and low BMI based on the level of food reinforcement, while the diathesis stress or dual-gain model only influences one end of the outcome measure. The interaction with MAOA-LPR better fits the diathesis stress model, with the 3.5R/4R allele conferring protection for individuals low in food reinforcement. These results provide new insight into genes theoretically involved in obesity, and support the hypothesis that genetics moderate the association between food reinforcement and BMI.
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Keith Babbs et al.
Physiology & Behavior, forthcoming
Abstract:
Previous investigations consistently report a negative association between body mass index (BMI) and response in the caudate nucleus during the consumption of palatable and energy dense food. Since this response has also been linked to weight gain, we sought to replicate this finding and determine if the reduced response is associated with measures of impulsivity or food reward. Two studies were conducted in which fMRI was used to measure brain response to milkshake and a tasteless control solution. In Study 1 (n = 25) we also assessed self-reported impulsivity, willingness to work for food, and subjective experiences of the pleasantness of milkshake taste and aroma. Replicating prior work, we report a negative association between BMI and brain response to milkshake vs. tasteless in the caudate nucleus. The opposite pattern was observed in the ventral putamen, with greater response observed in the 13 overweight compared to the 12 healthy weight subjects. Regression of brain response against impulsivity and food reward measures revealed one significant association: in the overweight but not healthy weight group self-reported impulsivity was negatively associated with caudate response to milkshake. In Study 2 (n = 14), in addition to assessing brain response to milkshake and tasteless solutions subjects completed a go/no-go task outside the scanner. As predicted, we identified an inverse relationship between caudate response to milkshake vs. tasteless and failure to inhibit responses on the no-go trials. We conclude that the inverse correlation between BMI and caudate response to milkshake is associated with impulsivity but not food reward. These findings suggest that response to milkshake in the dorsal striatum may be related to weight gain by promoting impulsive eating behavior.
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Wei He et al.
PLoS ONE, March 2013
Introduction: Chinese are reported to have a higher percent body fat (¿) and a higher percent trunk fat (%TF) than whites for a given body mass index (BMI). However, the associations of these ethnic differences in body composition with metabolic risks remain unknown.
Methods and Procedures: A total of 1 029 Chinese from Hangzhou, China, and 207 whites from New York, NY, USA, were recruited in the present study. Body composition was measured using dual-energy X-ray absorptiometry (DXA). Analysis of covariance was used to assess the ethnic differences in fat, fat distribution, and metabolic risk factors.
Results: After adjusting for BMI, age, and height, Chinese men had an average of 3.9% more ¿ and 12.1% more %TF than white men; Chinese women had an average of 2.3% more ¿ and 11.8% more %TF than white women. Compared with whites, higher metabolic risks were detected in Chinese for a given BMI after adjusting for age and height. Further adjustment for ¿ did not change these ethnic disparities. However, after adjusting for %TF, the ethnic differences decreased and become insignificant in triglyceride, high-density lipoprotein cholesterol, and blood pressure (except for systolic blood pressure in men). For fasting plasma glucose, the ethnic differences persisted after adjustment for ¿, but decreased significantly from 0.910 to 0.686 mmol/L among men, and from 0.629 to 0.355 mmol/L among women, when the analyses were further controlled for %TF.
Discussion: Chinese have both higher ¿ and %TF than white people for a given BMI. However, only %TF could in part account for the higher metabolic risk observed in Chinese men and women.
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Timing of Solid Food Introduction and Obesity: Hong Kong's "Children of 1997" Birth Cohort
Shi Lin Lin et al.
Pediatrics, forthcoming
Background: Some observational studies in Western settings show that early introduction of solid food is associated with subsequent obesity. However, introduction of solid food and obesity share social patterning. We examined the association of the timing of the introduction of solid food with BMI and overweight (including obesity) into adolescence in a developed non-Western setting, in which childhood obesity is less clearly socially patterned.
Methods: We used generalized estimating equation models to estimate the adjusted associations of the timing of the introduction of solid food (<3, 3-4, 5-6, 7-8, and >8 months) with BMI z score and overweight (including obesity) at different growth phases (infancy, childhood, and puberty) in 7809 children (88% follow-up) from a Chinese birth cohort, "Children of 1997." We assessed if the associations varied with gender or breastfeeding. We used multiple imputation for missing exposure and confounders.
Results: The introduction of solid food at <3 months of age was associated with lower family socioeconomic position (SEP) but was not clearly associated with BMI or overweight (including obesity) in infancy [mean difference in BMI z score: 0.01; 95% confidence interval (CI): -0.14 to 0.17], childhood (0.14; 95% CI: -0.11 to 0.40), or at puberty (0.22; 95% CI: -0.07 to 0.52), adjusted for SEP and infant and maternal characteristics.
Conclusions: In a non-Western developed setting, there was no clear association of the early introduction of solid food with childhood obesity. Together with the inconsistent evidence from studies in Western settings, this finding suggests that any observed associations might simply be residual confounding by SEP.
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Richard Martin et al.
Journal of the American Medical Association, 13 March 2013, Pages 1005-1013
Importance: Evidence that longer-term and exclusive breastfeeding reduces child obesity risk is based on observational studies that are prone to confounding.
Objective: To investigate effects of an intervention to promote increased duration and exclusivity of breastfeeding on child adiposity and circulating insulin-like growth factor (IGF)-I, which regulates growth.
Design, Setting, and Participants: Cluster-randomized controlled trial in 31 Belarusian maternity hospitals and their affiliated clinics, randomized into 1 of 2 groups: breastfeeding promotion intervention (n = 16) or usual practices (n = 15). Participants were 17 046 breastfeeding mother-infant pairs enrolled in 1996 and 1997, of whom 13 879 (81.4%) were followed up between January 2008 and December 2010 at a median age of 11.5 years.
Intervention: Breastfeeding promotion intervention modeled on the WHO/UNICEF Baby-Friendly Hospital Initiative (World Health Organization/United Nations Children's Fund).
Main Outcome Measures: Body mass index (BMI), fat and fat-free mass indices (FMI and FFMI), percent body fat, waist circumference, triceps and subscapular skinfold thicknesses, overweight and obesity, and whole-blood IGF-I. Primary analysis was based on modified intention-to-treat (without imputation), accounting for clustering within hospitals and clinics.
Results: The experimental intervention substantially increased breastfeeding duration and exclusivity when compared with the control (43% vs 6% exclusively breastfed at 3 months and 7.9% vs 0.6% at 6 months). Cluster-adjusted mean differences in outcomes at 11.5 years of age between experimental vs control groups were: 0.19 (95% CI, -0.09 to 0.46) for BMI; 0.12 (-0.03 to 0.28) for FMI; 0.04 (-0.11 to 0.18) for FFMI; 0.47% (-0.11% to 1.05%) for percent body fat; 0.30 cm (-1.41 to 2.01) for waist circumference; -0.07 mm (-1.71 to 1.57) for triceps and -0.02 mm (-0.79 to 0.75) for subscapular skinfold thicknesses; and -0.02 standard deviations (-0.12 to 0.08) for IGF-I. The cluster-adjusted odds ratio for overweight/obesity (BMI ≥85th vs <85th percentile) was 1.18 (95% CI, 1.01 to 1.39) and for obesity (BMI ≥95th vs <85th percentile) was 1.17 (95% CI, 0.97 to 1.41).
Conclusions and Relevance: Among healthy term infants in Belarus, an intervention that succeeded in improving the duration and exclusivity of breastfeeding did not prevent overweight or obesity, nor did it affect IGF-I levels at age 11.5 years. Breastfeeding has many advantages but population strategies to increase the duration and exclusivity of breastfeeding are unlikely to curb the obesity epidemic.
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Jessica McNeil et al.
Physiology & Behavior, 15 March 2013, Pages 84-89
Abstract:
Increases in energy, lipid and carbohydrate intakes during the luteal phase have been previously observed. However, it is not known whether this is due to phase-dependent variations in the reward value of certain foods. Moreover, increases in olfactory sensitivity have been proposed and may be involved in these changes in food reward. Therefore, we examined olfactory performance and the reward value of foods varying in fat content and taste. Seventeen women (Body mass index: 22.3 ± 1.6 kg/m2; Body fat-DXA: 28.5 ± 6.8%) were recruited to participate in 3 identical sessions, performed during distinct phases of the menstrual cycle - early follicular/menstruation, late follicular/ovulation and mid-luteal - verified by plasma sex-steroid hormones and oral temperature. Food preference, implicit wanting, and explicit wanting and liking for visual food cues, varying in fat content and taste, were measured with a validated experimental platform involving a forced choice computer task. Odour threshold, odour discrimination, odour identification and total odour scores were measured using odourized pens. Ad libitum energy and macronutrient intakes was measured with a validated food menu. Results showed greater total odour scores (p < 0.05), explicit wanting for high fat foods (p < 0.05) and lipid intake (p < 0.05) during the mid-luteal phase. Inter-correlations between these variables were non-significant. These findings support previous observations of increased lipid intake during the luteal phase and provide evidence for phase-dependent variation in overall olfactory performance and explicit wanting for high fat foods.
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Perceived Environmental Church Support and Physical Activity Among Black Church Members
Meghan Baruth et al.
Health Education & Behavior, forthcoming
Background: Churches are an appealing setting for implementing health-related behavior change programs. Purpose. The objective of the study was to examine the relationship between perceived environmental church support for physical activity (PA) and PA behaviors.
Method: Black church members from South Carolina (n = 309) wore an Actigraph accelerometer prior to the initiation of an intervention. Relationships between moderate to vigorous PA (MVPA; counts ≥1,952), light PA (LPA; counts 100-1951), sedentary behavior (counts <100), and perceived environmental church support for PA (total, spoken informational, written informational, instrumental) were examined. Support × Gender interactions examined whether relationships differed by gender.
Results: The mean age was 54.0 ± 12.3 years and mean body mass index was 32.9 ± 7.2 kg/m2. On average, participants engaged in 14.4 ± 13.7 minutes/day of MVPA, 289.8 ± 82.4 minutes/day of LPA, and were sedentary 548.9 ± 102.2 minutes/day. Total, spoken informational, and written informational church support were significantly related to higher levels of LPA and lower levels of sedentary behavior in men but not women. The relationship between written informational support and MVPA approached significance for men but not women. Instrumental church support was not associated with PA behaviors.
Conclusion: The church environment may have an important influence on Black church members' PA behavior, particularly men's, and thus should be targeted in interventions.
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R. Mathur et al.
Journal of Clinical Endocrinology & Metabolism, April 2013, Pages E698-E702
Context: Colonization of the gastrointestinal tract with methanogenic archaea (methanogens) significantly affects host metabolism and weight gain in animal models, and breath methane is associated with a greater body mass index (BMI) among obese human subjects.
Objective: The objective of the study was to characterize the relationship between methane and hydrogen on breath test (as a surrogate for colonization with the hydrogen requiring methanogen, Methanobrevibacter smithii), body weight, and percent body fat in a general population cohort.
Design and Subjects: This was a prospective study (n = 792) of consecutive subjects presenting for breath testing.
Setting: The study was conducted at a tertiary care center.
Outcome Measurements: BMI and percent body fat were measured.
Results: Subjects were classified into 4 groups based on breath testing: normal (N) (methane <3 ppm and hydrogen <20 ppm at or before 90 minutes); hydrogen positive only (H+) [methane <3 ppm and hydrogen ≥20 ppm); methane positive only (M+) (methane ≥3 ppm and hydrogen <20 ppm), or methane and hydrogen positive (M+/H+) (methane ≥3 ppm and hydrogen ≥20 ppm]. There were significant differences in age but not in gender across the groups. After controlling for age as a confounding variable, M+/H+ subjects had significantly higher BMI than other groups (N: 24.1 ± 5.2 kg/m2; H+: 24.2 ± 4.5 kg/m2; M+: 24.0 ± 3.75 kg/m2; M+/H+: 26.5 ± 7.1 kg/m2, P < .02) and also had significantly higher percent body fat (N: 28.3 ± 10.0%; H+: 27.5 ± 9.0%; M+: 28.0 ± 8.9%; M+/H+; 34.1 ± 10.9%, P < .001).
Conclusions: The presence of both methane and hydrogen on breath testing is associated with increased BMI and percent body fat in humans. We hypothesize that this is due to colonization with the hydrogen-requiring M smithii, which affects nutrient availability for the host and may contribute to weight gain.
Sunday, April 14, 2013
How you can help
Life or Death Decisions: Framing the Call for Help
Eileen Chou & Keith Murnighan
PLoS ONE, March 2013
Background: Chronic blood shortages in the U.S. would be alleviated by small increases, in percentage terms, of people donating blood. The current research investigated the effects of subtle changes in charity-seeking messages on the likelihood of people responses to a call for help. We predicted that "avoid losses" messages would lead to more helping behavior than "promote gains" messages would.
Method: Two studies investigated the effects of message framing on helping intentions and behaviors. With the help and collaboration of the Red Cross, Study 1, a field experiment, directly assessed the effectiveness of a call for blood donations that was presented as either death-preventing (losses) or life-saving (gains), and as being of either more or less urgent need. With the help and collaboration of a local charity, Study 2, a lab experiment, assessed the effects of the gain-versus-loss framing of a donation-soliciting flyer on individuals' expectations of others' monetary donations as well their own volunteering behavior. Study 2 also assessed the effects of three emotional motivators - feelings of empathy, positive affect, and relational closeness.
Result: Study 1 indicated that, on a college campus, describing blood donations as a way to "prevent a death" rather than "save a life" boosted the donation rate. Study 2 showed that framing a charity's appeals as helping people to avoid a loss led to larger expected donations, increased intentions to volunteer, and more helping behavior, independent of other emotional motivators.
Conclusion: This research identifies and demonstrates a reliable and effective method for increasing important helping behaviors by providing charities with concrete ideas that can effectively increase helping behavior generally and potentially death-preventing behavior in particular.
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The multidimensional effects of a small gift: Evidence from a natural field experiment
Ellen Garbarino, Robert Slonim & Carmen Wang
Economics Letters, forthcoming
Abstract:
Using a large natural field experiment, we demonstrate that a small unconditional gift (pen) more than doubled both small (survey) and large (blood donation) responses. We find no evidence that the opportunity for a small response crowded out the larger response; asking participants to also complete a survey directionally increased donations.
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Induced Altruism in Religious, Military, and Terrorist Organizations
Hector Qirko
Cross-Cultural Research, May 2013, Pages 131-161
Abstract:
Human altruism in non-kin, unreciprocated contexts is difficult to understand in evolutionary terms. However, neo-Darwinian theories remain a potentially useful means of illuminating this behavior. In particular, induced altruism, wherein cues of genetic relatedness are manipulated to elicit costly behaviors for the benefit of non-kin, appears highly relevant. This article reviews cross-cultural data on several examples of extremely costly altruism - vows of celibacy, suicide bombings, and combat suicide - as exhibited in organizational and institutional contexts. Two predictions are used to test the relevance of induced altruism to the reinforcement of altruistic commitment to these behaviors. First, different organizations requiring costly sacrifice by their members should employ similar practices involving patterns of association, phenotypic similarity, and kinship terminology that are associated with kin cue-manipulation. Second, these organizational practices should be adopted as a consequence of recruit pools growing increasingly larger and, thus, less genetically related. There appears to be support for both predictions, suggesting that cross-cultural analyses could provide an effective avenue through which to test this and other evolutionary theories related to human unreciprocated altruism in non-kin contexts.
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Jonathan Meer
Economic Inquiry, forthcoming
Abstract:
Many charitable organizations believe it is worthwhile to solicit very small donations, particularly from young people, because these gifts form a habit of giving which leads to larger donations in the future. Indeed, there is some evidence of a positive correlation between giving when young and giving when old. However, such a correlation, by itself, does not constitute evidence of habit formation. Using data on alumni contributions to a university, we assess whether the correlation is due to habit formation - true state dependence - or to unobservable factors such as affinity to the school. We further examine whether habits form by the mere act of giving or based on the amount given. We implement an instrumental variables approach using the fact that performance of the school's athletic teams and solicitation by one's former roommates generate shocks to giving while young that are plausibly uncorrelated with giving when older. There is strong evidence of habit formation on the extensive margin, but not in the amount given. This finding has important implications for fundraising strategies, charities' accounting practices, and tax policy.
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Being Mimicked Increases Prosocial Behavior in 18-Month-Old Infants
Malinda Carpenter, Johanna Uebel & Michael Tomasello
Child Development, forthcoming
Abstract:
Most previous research on imitation in infancy has focused on infants' learning of instrumental actions on objects. This study focused instead on the more social side of imitation, testing whether being mimicked increases prosocial behavior in infants, as it does in adults (van Baaren, Holland, Kawakami, & van Knippenberg, 2004). Eighteen-month-old infants (N = 48) were either mimicked or not by an experimenter; then either that experimenter or a different adult needed help. Infants who had previously been mimicked were significantly more likely to help both adults than infants who had not been mimicked. Thus, even in infancy, mimicry has positive social consequences: It promotes a general prosocial orientation toward others.
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Experimental Evidence of Self-Image Concerns as Motivation for Giving
Mirco Tonin & Michael Vlassopoulos
Journal of Economic Behavior & Organization, June 2013, Pages 19-27
Abstract:
In this paper we present evidence of self-image concerns in charitable giving using a laboratory experiment. Subjects make a series of three decisions of allocating an endowment of £ 10 between themselves and a passive recipient that is either a charity or the experimenters. When making these decisions subjects are informed that one of them will be chosen randomly at the end to determine payoffs. After all decisions have been made and it has been revealed which decision will determine payoffs we offer subjects an opportunity to opt out from their initial decision and receive £ 10 instead. We find that almost a quarter of subjects choose to opt out, while around one third opt out from a positive donation. The fact that a subject decides to revise a decision to give and chooses instead to keep the whole amount - an option that was available when she made the first decision and was not exercised - indicates that giving in the first instance was not motivated solely by altruism toward the recipient. We argue that opting out can be explained through a combination of a reduced benefit of self-signaling due to satiation, and an increase in the costs of giving at the opt out stage, as they are realized with certainty.
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Volunteering Predicts Health Among Those Who Value Others: Two National Studies
Michael Poulin
Health Psychology, forthcoming
Objective: The purpose of these studies was to examine the role of positive views of other people in predicting stress-buffering effects of volunteering on mortality and psychological distress.
Method: In Study 1, stressful life events, volunteering, and hostile cynicism assessed in a baseline Detroit-area survey (N = 846) predicted survival over a 5-year period, adjusting for relevant covariates. In Study 2, stressful life events, volunteering, and world benevolence beliefs assessed in a baseline national survey (N = 1,157) predicted psychological distress over a 1-year period, adjusting for distress at baseline.
Results: In Study 1, a Cox proportional hazard model indicated that for individuals low in cynicism, stress predicted mortality at low levels of volunteering but not at high levels of volunteering. This effect was not present among those high in cynicism. In Study 2, multiple regression analysis revealed that among individuals high in world benevolence beliefs, stress predicted elevated distress at low levels of volunteering but not at high levels of volunteering. This effect was absent for those lower in world benevolence beliefs.
Conclusions: Consistent with prior research on helping behavior, these studies indicate that helping behavior can buffer the effects of stress on health. However, the results of these studies indicate that stress-buffering effects of volunteering are limited to individuals with positive views of other people. Not all individuals may benefit from volunteering, and health-promotion efforts seeking to draw on health benefits of helping behavior may need to target their approach accordingly.
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The bystander effect in an N-person dictator game
Karthik Panchanathan, Willem Frankenhuis & Joan Silk
Organizational Behavior and Human Decision Processes, March 2013, Pages 285-297
Abstract:
Dozens of studies show that bystanders are less likely to help victims as bystander number increases. However, these studies model one particular situation, in which victims need only one helper. Using a multi-player dictator game, we study a different but common situation, in which a recipient's welfare increases with the amount of help, and donors can share the burden of helping. We find that dictators transfer less when there are more dictators, and recipients earn less when there are multiple dictators. This effect persisted despite mechanisms eliminating uncertainty about other dictators' behavior (a strategy method and communication). In a typical public goods game, people seem to transform the situation into an assurance game, willing to contribute if certain others will too. Despite similarities, people do not treat a recipient's welfare like a public good. Instead, people seem to transform the situation into a prisoner's dilemma, refusing to help whatever others do.
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Morten Brænder & Lotte Bøgh Andersen
Public Administration Review, forthcoming
Abstract:
Exposure to the extreme stress of warfare may affect soldiers' perceptions of others and society. Using panel data from two companies on a tour of duty to Afghanistan in 2011, this article analyzes how different dimensions of soldiers' public service motivation are influenced by deployment to war. As expected, soldiers' compassion decreased and commitment to the public interest increased, while self-sacrifice did not change systematically. Deployment to war was expected to affect inexperienced soldiers more than their experienced colleagues, but this hypothesis was only partially satisfied. The key contribution of the article is the use of panel data and the examination of motivational changes. Moreover, studying soldiers' public service motivation enables us to connect public administration and military sociology and thereby to establish a better understanding of motivation in extreme settings.
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A comparison of Asians', Hispanics', and Whites' restaurant tipping
Michael Lynn
Journal of Applied Social Psychology, April 2013, Pages 834-839
Abstract:
Asians and Hispanics are perceived by many restaurant servers as poor tippers. This study tests the validity of those perceptions using data from a large restaurant chain's online customer satisfaction survey. Findings partially support servers' perceptions - Hispanics but not Asians tipped less on average than Whites after controlling for bill size, the customer's own ratings of service quality, and other variables. Discussion centers around the differences between these findings and those of a previous study and on the practical implications of the findings for restaurant managers.
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Tehila Kogut & Ehud Kogut
Journal of Experimental Social Psychology, forthcoming
Abstract:
People's preference to help victims about whom they have some information is known as the identifiable victim effect. Results of three studies, in which dispositional attachment styles were measured (study 1) and activated in a between-subjects priming manipulation (studies 2 and 3), suggest that the intensity of this phenomenon is related to the potential helper's adult attachment style. Specifically, we found that secure people provide similar levels of help to identified and unidentified victims. Attachment avoidance is associated with lower donations to both types of victims. Finally, the biggest gap between donations to identified and unidentified victims was found for anxious people, who tend to donate relatively higher amounts to identified victims and lower amounts to unidentified ones. Moreover, people under attachment-anxiety priming tend to perceive less similarity and connectedness between themselves and unidentified victims as opposed to identified victims, a tendency that may underlie the identifiability effect.
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Caring for sharing: How attachment styles modulate communal cues of physical warmth
Hans IJzerman et al.
Social Psychology, Spring 2013, Pages 160-166
Abstract:
Does physical warmth lead to caring and sharing? Research suggests that it does; physically warm versus cold conditions induce prosocial behaviors and cognitions. Importantly, previous research has not traced the developmental origins of the association between physical warmth and affection. The association between physical warmth and sharing may be captured in specific cognitive models of close social relations, often referred to as attachment styles. In line with this notion, and using a dictator game set-up, the current study demonstrates that children who relate to their friends with a secure attachment style are more generous toward their peers in warm than in cold conditions. This effect was absent for children who relate to friends with an insecure attachment style. Notably, however, these children not just always shared less: They allocated more stickers to a friend than to a stranger. These findings provide an important first step to understand how fundamental embodied relations develop early in life. We discuss broader implications for grounded cognition and person perception.
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Hannah Schreier, Kimberly Schonert-Reichl & Edith Chen
JAMA Pediatrics, April 2013, Pages 327-332
Importance: The idea that individuals who help others incur health benefits themselves suggests a novel approach to improving health while simultaneously promoting greater civic orientation in our society. The present study is the first experimental trial, to our knowledge, of whether regular volunteering can reduce cardiovascular risk factors in adolescents.
Objective: To test a novel intervention that assigned adolescents to volunteer with elementary school-aged children as a means of improving adolescents' cardiovascular risk profiles.
Design: Randomized controlled trial, with measurements taken at baseline and 4 months later (postintervention).
Setting: Urban public high school in western Canada.
Participants: One hundred six 10th-grade high school students who were fluent in English and free of chronic illnesses.
Intervention: Weekly volunteering with elementary school-aged children for 2 months vs wait-list control group.
Main Outcome Measures: Cardiovascular risk markers of C-reactive protein level, interleukin 6 level, total cholesterol level, and body mass index.
Results: No statistically significant group differences were found at baseline. Postintervention, adolescents in the intervention group showed significantly lower interleukin 6 levels (log10 mean difference, 0.13; 95% CI, 0.004 to 0.251), cholesterol levels (log10 mean difference, 0.03; 95% CI, 0.003 to 0.059), and body mass index (mean difference, 0.39; 95% CI, 0.07 to 0.71) compared with adolescents in the control group. Effects for C-reactive protein level were marginal (log10 mean difference, 0.13; 95% CI, -0.011 to 0.275). Preliminary analyses within the intervention group suggest that those who increased the most in empathy and altruistic behaviors, and who decreased the most in negative mood, also showed the greatest decreases in cardiovascular risk over time.
Conclusions and Relevance: Adolescents who volunteer to help others also benefit themselves, suggesting a novel way to improve health.
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Michael Babula
Journal of Applied Social Psychology, April 2013, Pages 899-908
Abstract:
The helping motivations of wealth-driven college students were investigated. Tang et al. argues that wealth-driven individuals are extrinsically motivated, and that extrinsic motivation negatively relates to helping behavior. The results of questionnaires and experimentation here contradict the recent literature. Seventy-two percent of subjects reported wealth as a top priority in life. Fifty-six percent of subjects would take an insider trading tip, and 78% of subjects offered help to a confederate who just learned his family member was in an accident and needed to make a telephone call. Logistic regression results showed intrinsic motivation among participants significantly predicted increased helping behavior. It is recommended that surveys used to create new paradigms be followed up with experimentation whenever feasible.
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Ease of retrieval and the moral circle
Simon Laham
Social Psychology, Winter 2013, Pages 33-36
Abstract:
Two studies demonstrate that the ease with which moral circle exemplars come to mind influences the size of the moral circle and moral behavior. Participants who generated three exemplars had significantly larger circles than those asked to generate 15. Further, those who generated three exemplars were more likely to take a newsletter providing information on how to help circle members. These studies demonstrate the impact of metacognitive experiences on moral judgment and behavior, and highlight the importance of including metacognitive variables in any comprehensive account of moral judgment.
Saturday, April 13, 2013
Will do
Petra Schmid & Marianne Schmid Mast
European Journal of Social Psychology, April 2013, Pages 201-211
Abstract:
We tested whether power reduces responses related to social stress and thus increases performance evaluation in social evaluation situations. We hypothesized and found that thinking about having power reduced fear of negative evaluation and physiological arousal during a self-presentation task (Studies 1 and 2). In Study 2, we also showed that simply thinking about having power made individuals perform better in a social evaluation situation. Our results confirmed our hypotheses that the mechanism explaining this power-performance link was that high power participants felt less fear of negative evaluation. The reduced fear of negative evaluation generated fewer signs of behavioral nervousness, which caused their performance to be evaluated more positively (serial mediation). Simply thinking of having power can therefore have important positive consequences for a person in an evaluation situation in terms of how he or she feels and how he or she is evaluated.
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Money and the fear of death: The symbolic power of money as an existential anxiety buffer
Tomasz Zaleskiewicz et al.
Journal of Economic Psychology, June 2013, Pages 55-67
Abstract:
According to terror management theory, people deal with the potential for anxiety that results from their knowledge of the inevitability of death by holding on to sources of value that exist within their cultural worldview. We propose that money is one such source capable of soothing existential anxiety. We hypothesize that death anxiety would amplify the value attributed to money, and that the presence of money would alleviate death anxiety. Study 1 indicated that individuals reminded of their mortality overestimated the size of coins and monetary notes. In Study 2, participants induced to think about their mortality used higher monetary standards to define a person or family as rich than those in the control condition. Study 3 revealed that people reminded of death desired higher compensation for waiving the immediate payment of money. Finally, Study 4 showed that priming participants with the concept of money reduced self-reported fear of death. We conclude that, beyond its pragmatic utility, money possesses a strong psychological meaning that helps to buffer existential anxiety.
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Priming motivation through unattended speech
Rémi Radel et al.
British Journal of Social Psychology, forthcoming
Abstract:
This study examines whether motivation can be primed through unattended speech. Study 1 used a dichotic-listening paradigm and repeated strength measures. In comparison to the baseline condition, in which the unattended channel was only composed by neutral words, the presence of words related to high (low) intensity of motivation led participants to exert more (less) strength when squeezing a hand dynamometer. In a second study, a barely audible conversation was played while participants' attention was mobilized on a demanding task. Participants who were exposed to a conversation depicting intrinsic motivation performed better and persevered longer in a subsequent word-fragment completion task than those exposed to the same conversation made unintelligible. These findings suggest that motivation can be primed without attention.
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Your Right Arm for a Publication in AER?
Arthur Attema, Werner Brouwer & Job Van Exel
Economic Inquiry, forthcoming
Abstract:
The time tradeoff (TTO) method is popular in medical decision making for valuing health states. We use it to elicit economists' preferences for publishing in top economic journals and for living without limbs. The economists value journal publications highly and have a clear preference among them, with the American Economic Review (AER) the most preferred. Their responses imply they would sacrifice more than half a thumb for an AER publication. These TTO results are consistent with ranking and willingness to pay results, and indicate that journal preferences are not entirely determined by impact factors or by expectations of a salary increase following a publication in a prestigious journal.
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Children with autism can track others' beliefs in a competitive game
Candida Peterson et al.
Developmental Science, forthcoming
Abstract:
Theory of mind (ToM) development, assessed via ‘litmus' false belief tests, is severely delayed in autism, but the standard testing procedure may underestimate these children's genuine understanding. To explore this, we developed a novel test involving competition to win a reward as the motive for tracking other players' beliefs (the ‘Dot-Midge task'). Ninety-six children, including 23 with autism (mean age: 10.36 years), 50 typically developing 4-year-olds (mean age: 4.40) and 23 typically developing 3-year-olds (mean age: 3.59) took a standard ‘Sally-Ann' false belief test, the Dot-Midge task (which was closely matched to the Sally-Ann task procedure) and a norm-referenced verbal ability test. Results revealed that, of the children with autism, 74% passed the Dot-Midge task, yet only 13% passed the standard Sally-Ann procedure. A similar pattern of performance was observed in the older, but not the younger, typically developing control groups. This finding demonstrates that many children with autism who fail motivationally barren standard false belief tests can spontaneously use ToM to track their social partners' beliefs in the context of a competitive game.
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A psychological predictor of elders' driving performance: Social-comparisons on the road
Becca Levy et al.
Journal of Applied Social Psychology, March 2013, Pages 556-561
Abstract:
Older individuals often believe they can drive better than their contemporaries. This belief is an example of downward social-comparisons; they can be self-enhancing tools that lead to beneficial outcomes. As predicted, we found that drivers who engaged in downward social-comparisons were significantly less likely to have adverse driving events over time, after controlling for relevant factors (p = .02). This effect was particularly strong among women, who tend to experience more negative driving stereotypes (p = .01). The study was based on 897 interviews of 117 elder drivers, aged 70-89 years, over 2 years. Our findings suggest that interventions to reduce adverse driving events among elders could benefit from including a psychological component.
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To pay or not to pay? Do extrinsic incentives alter the Köhler group motivation gain?
Norbert Kerr, Deborah Feltz & Brandon Irwin
Group Processes & Intergroup Relations, March 2013, Pages 257-268
Abstract:
The Köhler effect is an increase in task motivation that occurs in performance groups when one is (a) less capable than one's fellow group members, and (b) one's efforts are particularly indispensible for group success. Recently, it has been shown that the Köhler effect can dramatically increase one's motivation to exercise. The present study examines the potential moderating effect of the provision of extrinsic incentives on such Köhler motivation gains. When participants were offered such an extrinsic incentive for persisting at an exercise task, a robust Köhler effect was observed - participants who thought they were the less capable member of a dyad working at a conjunctive-group exercise task persisted 26% longer than comparable individual exercisers. But an even stronger effect (a 43% improvement) was observed when no such incentive was on offer. Possible explanations and boundary conditions for this moderating effect are discussed.
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Breaking Monotony with Meaning: Motivation in Crowdsourcing Markets
Dana Chandler & Adam Kapelner
Journal of Economic Behavior & Organization, forthcoming
Abstract:
We conduct the first natural field experiment to explore the relationship between the "meaningfulness" of a task and worker effort. We employed about 2,500 workers from Amazon's Mechanical Turk (MTurk), an online labor market, to label medical images. Although given an identical task, we experimentally manipulated how the task was framed. Subjects in the meaningful treatment were told that they were labeling tumor cells in order to assist medical researchers, subjects in the zero-context condition (the control group) were not told the purpose of the task, and, in stark contrast, subjects in the shredded treatment were not given context and were additionally told that their work would be discarded. We found that when a task was framed more meaningfully, workers were more likely to participate. We also found that the meaningful treatment increased the quantity of output (with an insignificant change in quality) while the shredded treatment decreased the quality of output (with no change in quantity). We believe these results will generalize to other short-term labor markets. Our study also discusses MTurk as an exciting platform for running natural field experiments in economics.
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Keeping it real: Self-control depletion increases accuracy, but decreases confidence for performance
Amber DeBono & Mark Muraven
Journal of Applied Social Psychology, forthcoming
Abstract:
We propose that egotism about one's abilities may be related to good self-regulation and a lack of self-control may reduce estimations of aptitudes. Self-control depletion should lead to more accurate and therefore less lofty predictions of future performances. In two experiments, self-control depletion was manipulated by having participants either resist tempting cookies or by inhibiting thoughts about a white bear. In both cases, nondepleted participants made bolder predictions about their future performance on a video game than their depleted counterparts. Instead, depleted participants were more modest in their predictions and more accurate in their predictions than nondepleted participants. These findings suggest that depletion undermines self-assurance in oneself, which may have implications for theories of depressive realism, accuracy, confidence, and goal setting.
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Mental Contrasting Changes the Meaning of Reality
Andreas Kappes et al.
Journal of Experimental Social Psychology, forthcoming
Abstract:
Mental contrasting of a desired future with the present reality strengthens goal pursuit when expectations of success are high, and weakens goal pursuit when expectations of success are low. We hypothesized that mental contrasting effects on selective goal pursuit are mediated by a change in the meaning of the present reality as an obstacle towards reaching the desired future. Using explicit evaluation of reality (Study 1), implicit categorization of reality as obstacle (Study 2), and detection of obstacle (Study 3) as indicators, we found that mental contrasting (versus relevant control groups) fostered the meaning of reality as obstacle when expectations of success were high, but weakened it when expectations of success were low. Importantly, the meaning of reality as obstacle mediated mental contrasting effects on goal pursuit (Study 1, 2). The findings suggest that mental contrasting produces selective goal pursuit by changing the meaning of a person's reality.
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Time Pressure Undermines Performance More Under Avoidance Than Approach Motivation
Marieke Roskes et al.
Personality and Social Psychology Bulletin, forthcoming
Abstract:
Four experiments were designed to test the hypothesis that performance is particularly undermined by time pressure when people are avoidance motivated. The results supported this hypothesis across three different types of tasks, including those well suited and those ill suited to the type of information processing evoked by avoidance motivation. We did not find evidence that stress-related emotions were responsible for the observed effect. Avoidance motivation is certainly necessary and valuable in the self-regulation of everyday behavior. However, our results suggest that given its nature and implications, it seems best that avoidance motivation is avoided in situations that involve (time) pressure.
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Mario Wenzel, Tamlin Conner & Thomas Kubiak
European Journal of Social Psychology, April 2013, Pages 175-184
Abstract:
Performing consecutive self-control tasks typically leads to deterioration in self-control performance. This effect can be explained within the strength model of self-control or within a cognitive control perspective. Both theoretical frameworks differ in their predictions with regard to the impact of affect and task characteristics on self-control deterioration within a two-task paradigm. Whereas the strength model predicts decrements in self-control performance whenever both tasks require a limited resource, under a cognitive control perspective, decrements should only occur when people switch to a different response conflict in the second task. Moreover, only the cognitive control model predicts an interaction between task switching and positive affect. In the present research, we investigated this interaction within a two-task paradigm and found evidence that favored a cognitive control interpretation of the results. Positive affect only benefitted consecutive self-control performance if response conflicts in the two tasks were different (resisting sweets followed by a Stroop task). If they were the same (two consecutive Stroop tasks), positive affect impaired self-control performance. These effects were partially replicated in the second study that also examined negative affect, which did not affect self-control performance. We conclude that drawing on cognitive control models could add substantially to research on self-control.
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Implicit Attitudes Toward the Self Over Time
Johanna Peetz, Christian Jordan & Anne Wilson
Self and Identity, forthcoming
Abstract:
Three studies examined whether people hold meaningful implicit attitudes toward future selves. Two approaches to measuring implicit future self-esteem were developed (individualized and generic Implicit Association Tests) and attitudes toward the self in ten (Studies 1 and 2) or one years' time (Study 3) were assessed. We predicted that implicit future self-esteem would be less strongly influenced by self-enhancement and wishful thinking than explicit future self-esteem. Consistent with this expectation, people's explicit self-esteem was more positive toward their future than their current self, whereas implicit future self-esteem was not enhanced relative to the present. As expected, implicit (but not explicit) future self-esteem predicted academic and health motivation, as well as greater elaboration of, and more structure in, future goals. In contrast, explicit (but not implicit) future self-esteem predicted future-oriented measures more linked to wishful thinking: positive fantasies and general optimism. These results suggest that implicit future self-esteem is meaningfully distinct from explicit future self-esteem and has implications for motivation and goals.
Friday, April 12, 2013
If you can't take the heat
Climate Amenities, Climate Change, and American Quality of Life
David Albouy et al.
NBER Working Paper, March 2013
Abstract:
We present a hedonic framework to estimate U.S. households' preferences over local climates, using detailed weather and 2000 Census data. We find that Americans favor an average daily temperature of 65 degrees Fahrenheit, will pay more on the margin to avoid excess heat than cold, and are not substantially more averse to extremes than to temperatures that are merely uncomfortable. These preferences vary by location due to sorting or adaptation. Changes in climate amenities under business-as-usual predictions imply annual welfare losses of 1 to 3 percent of income by 2100, holding technology and preferences constant.
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Stephan Lewandowsky, Klaus Oberauer & Gilles Gignac
Psychological Science, forthcoming
Abstract:
Although nearly all domain experts agree that carbon dioxide emissions are altering the world's climate, segments of the public remain unconvinced by the scientific evidence. Internet blogs have become a platform for denial of climate change, and bloggers have taken a prominent role in questioning climate science. We report a survey of climate-blog visitors to identify the variables underlying acceptance and rejection of climate science. Our findings parallel those of previous work and show that endorsement of free-market economics predicted rejection of climate science. Endorsement of free markets also predicted the rejection of other established scientific findings, such as the facts that HIV causes AIDS and that smoking causes lung cancer. We additionally show that, above and beyond endorsement of free markets, endorsement of a cluster of conspiracy theories (e.g., that the Federal Bureau of Investigation killed Martin Luther King, Jr.) predicted rejection of climate science as well as other scientific findings. Our results provide empirical support for previous suggestions that conspiratorial thinking contributes to the rejection of science. Acceptance of science, by contrast, was strongly associated with the perception of a consensus among scientists.
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The pivotal role of perceived scientific consensus in acceptance of science
Stephan Lewandowsky, Gilles Gignac & Samuel Vaughan
Nature Climate Change, April 2013, Pages 399-404
Abstract:
Although most experts agree that CO2 emissions are causing anthropogenic global warming (AGW), public concern has been declining. One reason for this decline is the ‘manufacture of doubt' by political and vested interests, which often challenge the existence of the scientific consensus. The role of perceived consensus in shaping public opinion is therefore of considerable interest: in particular, it is unknown whether consensus determines people's beliefs causally. It is also unclear whether perception of consensus can override people's ‘worldviews', which are known to foster rejection of AGW. Study 1 shows that acceptance of several scientific propositions - from HIV/AIDS to AGW - is captured by a common factor that is correlated with another factor that captures perceived scientific consensus. Study 2 reveals a causal role of perceived consensus by showing that acceptance of AGW increases when consensus is highlighted. Consensus information also neutralizes the effect of worldview.
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A Reconstruction of Regional and Global Temperature for the Past 11,300 Years
Shaun Marcott et al.
Science, 8 March 2013, Pages 1198-1201
Abstract:
Surface temperature reconstructions of the past 1500 years suggest that recent warming is unprecedented in that time. Here we provide a broader perspective by reconstructing regional and global temperature anomalies for the past 11,300 years from 73 globally distributed records. Early Holocene (10,000 to 5000 years ago) warmth is followed by ~0.7°C cooling through the middle to late Holocene (<5000 years ago), culminating in the coolest temperatures of the Holocene during the Little Ice Age, about 200 years ago. This cooling is largely associated with ~2°C change in the North Atlantic. Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ~75% of the Holocene temperature history. Intergovernmental Panel on Climate Change model projections for 2100 exceed the full distribution of Holocene temperature under all plausible greenhouse gas emission scenarios.
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Projected Atlantic hurricane surge threat from rising temperatures
Aslak Grinsted, John Moore & Svetlana Jevrejeva
Proceedings of the National Academy of Sciences, 2 April 2013, Pages 5369-5373
Abstract:
Detection and attribution of past changes in cyclone activity are hampered by biased cyclone records due to changes in observational capabilities. Here, we relate a homogeneous record of Atlantic tropical cyclone activity based on storm surge statistics from tide gauges to changes in global temperature patterns. We examine 10 competing hypotheses using nonstationary generalized extreme value analysis with different predictors (North Atlantic Oscillation, Southern Oscillation, Pacific Decadal Oscillation, Sahel rainfall, Quasi-Biennial Oscillation, radiative forcing, Main Development Region temperatures and its anomaly, global temperatures, and gridded temperatures). We find that gridded temperatures, Main Development Region, and global average temperature explain the observations best. The most extreme events are especially sensitive to temperature changes, and we estimate a doubling of Katrina magnitude events associated with the warming over the 20th century. The increased risk depends on the spatial distribution of the temperature rise with highest sensitivity from tropical Atlantic, Central America, and the Indian Ocean. Statistically downscaling 21st century warming patterns from six climate models results in a twofold to sevenfold increase in the frequency of Katrina magnitude events for a 1 °C rise in global temperature (using BNU-ESM, BCC-CSM-1.1, CanESM2, HadGEM2-ES, INM-CM4, and NorESM1-M).
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Mark Jacobson et al.
Energy Policy, June 2013, Pages 585-601
Abstract:
This study analyzes a plan to convert New York State's (NYS's) all-purpose (for electricity, transportation, heating/cooling, and industry) energy infrastructure to one derived entirely from wind, water, and sunlight (WWS) generating electricity and electrolytic hydrogen. Under the plan, NYS's 2030 all-purpose end-use power would be provided by 10% onshore wind (4020 5-MW turbines), 40% offshore wind (12,700 5-MW turbines), 10% concentrated solar (387 100-MW plants), 10% solar-PV plants (828 50-MW plants), 6% residential rooftop PV (∼5 million 5-kW systems), 12% commercial/government rooftop PV (∼500,000 100-kW systems), 5% geothermal (36 100-MW plants), 0.5% wave (1910 0.75-MW devices), 1% tidal (2600 1-MW turbines), and 5.5% hydroelectric (6.6 1300-MW plants, of which 89% exist). The conversion would reduce NYS's end-use power demand ∼37% and stabilize energy prices since fuel costs would be zero. It would create more jobs than lost because nearly all NYS energy would now be produced in-state. NYS air pollution mortality and its costs would decline by ∼4000 (1200-7600) deaths/yr, and $33 (10-76) billion/yr (3% of 2010 NYS GDP), respectively, alone repaying the 271 GW installed power needed within ∼17 years, before accounting for electricity sales. NYS's own emission decreases would reduce 2050 U.S. climate costs by ∼$3.2 billion/yr.
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Assessment of the first consensus prediction on climate change
David Frame & Dáithí Stone
Nature Climate Change, April 2013, Pages 357-359
Abstract:
In 1990, climate scientists from around the world wrote the First Assessment Report of the Intergovernmental Panel on Climate Change. It contained a prediction of the global mean temperature trend over the 1990-2030 period that, halfway through that period, seems accurate. This is all the more remarkable in hindsight, considering that a number of important external forcings were not included. So how did this success arise? In the end, the greenhouse-gas-induced warming is largely overwhelming the other forcings, which are only of secondary importance on the 20-year timescale.
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The economic impact of climate change in the 20th and 21st centuries
Richard Tol
Climatic Change, April 2013, Pages 795-808
Abstract:
The national version of FUND3.6 is used to backcast the impacts of climate change to the 20th century and extrapolate to the 21st century. Carbon dioxide fertilization of crops and reduced energy demand for heating are the main positive impacts. Climate change had a negative effect on water resources and, in most years, human health. Most countries benefitted from climate change until 1980, but after that the trend is negative for poor countries and positive for rich countries. The global average impact was positive in the 20th century. In the 21st century, impacts turn negative in most countries, rich and poor. Energy demand, water resources, biodiversity and sea level rise are the main negative impacts; the impacts of climate change on human health and agriculture remain positive until 2100.
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Climate change, wine, and conservation
Lee Hannah et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
Climate change is expected to impact ecosystems directly, such as through shifting climatic controls on species ranges, and indirectly, for example through changes in human land use that may result in habitat loss. Shifting patterns of agricultural production in response to climate change have received little attention as a potential impact pathway for ecosystems. Wine grape production provides a good test case for measuring indirect impacts mediated by changes in agriculture, because viticulture is sensitive to climate and is concentrated in Mediterranean climate regions that are global biodiversity hotspots. Here we demonstrate that, on a global scale, the impacts of climate change on viticultural suitability are substantial, leading to possible conservation conflicts in land use and freshwater ecosystems. Area suitable for viticulture decreases 25% to 73% in major wine producing regions by 2050 in the higher RCP 8.5 concentration pathway and 19% to 62% in the lower RCP 4.5. Climate change may cause establishment of vineyards at higher elevations that will increase impacts on upland ecosystems and may lead to conversion of natural vegetation as production shifts to higher latitudes in areas such as western North America. Attempts to maintain wine grape productivity and quality in the face of warming may be associated with increased water use for irrigation and to cool grapes through misting or sprinkling, creating potential for freshwater conservation impacts. Agricultural adaptation and conservation efforts are needed that anticipate these multiple possible indirect effects.
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Your opinion on climate change might not be as common as you think
Z. Leviston, I. Walker & S. Morwinski
Nature Climate Change, April 2013, Pages 334-337
Abstract:
Political and media debate on the existence and causes of climate change has become increasingly factious in several western countries, often resting on claims and counter-claims about what most citizens really think. There are several well-established phenomena in psychology about how people perceive the prevalence of opinions, including the false consensus effect (a tendency to overestimate how common one's ‘own' opinion is) and pluralistic ignorance (where most people privately reject an opinion, but assume incorrectly that most others accept it). We investigated these biases in people's opinions about the existence and causes of climate change. In two surveys conducted 12 months apart in Australia (n = 5,036; n = 5,030), respondents were asked their own opinion about the nature of climate change, and then asked to estimate levels of opinion among the general population. We demonstrate that opinions about climate change are subject to strong false consensus effects, that people grossly overestimate the numbers of people who reject the existence of climate change in the broader community, and that people with high false consensus bias are less likely to change their opinions.
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External costs of nuclear: Greater or less than the alternatives?
Ari Rabl & Veronika Rabl
Energy Policy, June 2013, Pages 575-584
Abstract:
Since Fukushima many are calling for a shutdown of nuclear power plants. To see whether such a shutdown would reduce the risks for health and environment, the external costs of nuclear electricity are compared with alternatives that could replace it. The frequency of catastrophic nuclear accidents is based on the historical record, about one in 25 years for the plants built to date, an order of magnitude higher than the safety goals of the U.S. Nuclear Regulatory Commission. Impacts similar to Chernobyl and Fukushima are assumed to estimate the cost. A detailed comparison is presented with wind as alternative with the lowest external cost. The variability of wind necessitates augmentation by other sources, primarily fossil fuels, because storage at the required scale is in most regions too expensive. The external costs of natural gas combined cycle are taken as 0.6 €cent/kWh due to health effects of air pollution and 1.25 €cent/kWh due to greenhouse gases (at 25€/tCO2eq) for the central estimate, but a wide range of different parameters is also considered, both for nuclear and for the alternatives. Although the central estimate of external costs of the wind-based alternative is higher than that of nuclear, the uncertainty ranges overlap.
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Benjamin Preston
Global Environmental Change, forthcoming
Abstract:
Despite improvements in disaster risk management in the United States, a trend toward increasing economic losses from extreme weather events has been observed. This trend has been attributed to growth in socioeconomic exposure to extremes, a process characterized by strong path dependence. To understand the influence of path dependence on past and future losses, an index of potential socioeconomic exposure was developed at the U.S. county level based upon population size and inflation-adjusted wealth proxies. Since 1960, exposure has increased preferentially in the U.S. Southeast (particularly coastal and urban counties) and Southwest relative to the Great Plains and Northeast. Projected changes in exposure from 2009 to 2054 based upon scenarios of future demographic and economic change suggest a long-term commitment to increasing, but spatially heterogeneous, exposure to extremes, independent of climate change. The implications of this path dependence are examined in the context of several natural hazards. Using methods previously reported in the literature, annualized county-level losses from 1960 to 2008 for five climate-related natural hazards were normalized to 2009 values and then scaled based upon projected changes in exposure and two different estimates of the exposure elasticity of losses. Results indicate that losses from extreme events will grow by a factor of 1.3-1.7 and 1.8-3.9 by 2025 and 2050, respectively, with the exposure elasticity representing a major source of uncertainty. The implications of increasing physical vulnerability to extreme weather events for investments in disaster risk management are ultimately contingent upon the normative values of societal actors.
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The relationship between personal experience and belief in the reality of global warming
Teresa Myers et al.
Nature Climate Change, April 2013, Pages 343-347
Abstract:
In this paper, we address the chicken-or-egg question posed by two alternative explanations for the relationship between perceived personal experience of global warming and belief certainty that global warming is happening: Do observable climate impacts create opportunities for people to become more certain of the reality of global warming, or does prior belief certainty shape people's perceptions of impacts through a process of motivated reasoning? We use data from a nationally representative sample of Americans surveyed first in 2008 and again in 2011; these longitudinal data allow us to evaluate the causal relationships between belief certainty and perceived experience, assessing the impact of each on the other over time. Among the full survey sample, we found that both processes occurred: ‘experiential learning', where perceived personal experience of global warming led to increased belief certainty, and ‘motivated reasoning', where high belief certainty influenced perceptions of personal experience. We then tested and confirmed the hypothesis that motivated reasoning occurs primarily among people who are already highly engaged in the issue whereas experiential learning occurs primarily among people who are less engaged in the issue, which is particularly important given that approximately 75% of American adults currently have low levels of engagement.
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Michael Sivak
Environmental Research Letters, Winter 2013
Abstract:
Energy demand for climate control was analyzed for Miami (the warmest large metropolitan area in the US) and Minneapolis (the coldest large metropolitan area). The following relevant parameters were included in the analysis: (1) climatological deviations from the desired indoor temperature as expressed in heating and cooling degree days, (2) efficiencies of heating and cooling appliances, and (3) efficiencies of power-generating plants. The results indicate that climate control in Minneapolis is about 3.5 times as energy demanding as in Miami. This finding suggests that, in the US, living in cold climates is more energy demanding than living in hot climates.
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Recent temperature extremes at high northern latitudes unprecedented in the past 600 years
Martin Tingley & Peter Huybers
Nature, 11 April 2013, Pages 201-205
Abstract:
Recently observed extreme temperatures at high northern latitudes are rare by definition, making the longer time span afforded by climate proxies important for assessing how the frequency of such extremes may be changing. Previous reconstructions of past temperature variability have demonstrated that recent warmth is anomalous relative to preceding centuries or millennia, but extreme events can be more thoroughly evaluated using a spatially resolved approach that provides an ensemble of possible temperature histories. Here, using a hierarchical Bayesian analysis of instrumental, tree-ring, ice-core and lake-sediment records, we show that the magnitude and frequency of recent warm temperature extremes at high northern latitudes are unprecedented in the past 600 years. The summers of 2005, 2007, 2010 and 2011 were warmer than those of all prior years back to 1400 (probability P > 0.95), in terms of the spatial average. The summer of 2010 was the warmest in the previous 600 years in western Russia (P > 0.99) and probably the warmest in western Greenland and the Canadian Arctic as well (P > 0.90). These and other recent extremes greatly exceed those expected from a stationary climate, but can be understood as resulting from constant space-time variability about an increased mean temperature.
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Changing social contracts in climate-change adaptation
Neil Adger et al.
Nature Climate Change, April 2013, Pages 330-333
Abstract:
Risks from extreme weather events are mediated through state, civil society and individual action. We propose evolving social contracts as a primary mechanism by which adaptation to climate change proceeds. We use a natural experiment of policy and social contexts of the UK and Ireland affected by the same meteorological event and resultant flooding in November 2009. We analyse data from policy documents and from household surveys of 356 residents in western Ireland and northwest England. We find significant differences between perceptions of individual responsibility for protection across the jurisdictions and between perceptions of future risk from populations directly affected by flooding events. These explain differences in stated willingness to take individual adaptive actions when state support retrenches. We therefore show that expectations for state protection are critical in mediating impacts and promoting longer-term adaptation. We argue that making social contracts explicit may smooth pathways to effective and legitimate adaptation.
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Energy use and CO2 emissions of China's industrial sector from a global perspective
Sheng Zhou et al.
Energy Policy, forthcoming
Abstract:
The industrial sector has accounted for more than 50% of China's final energy consumption in the past 30 years. Understanding the future emissions and emissions mitigation opportunities depends on proper characterization of the present-day industrial energy use, as well as industrial demand drivers and technological opportunities in the future. Traditionally, however, integrated assessment research has handled the industrial sector of China in a highly aggregate form. In this study, we develop a technologically detailed, service-oriented representation of 11 industrial subsectors in China, and analyze a suite of scenarios of future industrial demand growth. We find that, due to anticipated saturation of China's per-capita demands of basic industrial goods, industrial energy demand and CO2 emissions approach a plateau between 2030 and 2040, then decrease gradually. Still, without emissions mitigation policies, the industrial sector remains heavily reliant on coal, and therefore emissions-intensive. With carbon prices, we observe some degree of industrial sector electrification, deployment of CCS at large industrial point sources of CO2 emissions at low carbon prices, an increase in the share of CHP systems at industrial facilities. These technological responses amount to reductions of industrial emissions (including indirect emission from electricity) are of 24% in 2050 and 66% in 2095.
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Trends in hourly rainfall statistics in the United States under a warming climate
T. Muschinski & J.I. Katz
Nature Climate Change, forthcoming
Abstract:
It is now widely accepted that the mean world climate has warmed since the beginning of climatologically significant anthropogenic emission of greenhouse gases. Warming may be accompanied by changes in the rate of extreme weather events such as severe storms and drought. Here we use hourly precipitation data from 13 stations in the 48 contiguous United States to determine trends in the frequency of such events, taking the normalized variance and a renormalized fourth moment of the precipitation measurements, averaged over decades, as objective measures of the frequency and severity of extreme weather. Using data mostly from the period 1940-1999 but also two longer data series, periods that include the rapid warming that seems to have begun at approximately 1970, we find a significant increase of 6.5±1.3%(1σ) per decade in the normalized variance at a site on the Olympic Peninsula at which it is low. We place statistical limits on any trend at the remaining 12 sites, where the normalized variance and its uncertainty are larger. At most sites these limits are consistent with the same rate of linear increase as at the Olympic Peninsula site, but exclude the same rate of percentage increase.
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Ocean acidification and its impacts: An expert survey
Jean-Pierre Gattuso, Katharine Mach & Granger Morgan
Climatic Change, April 2013, Pages 725-738
Abstract:
The oceans moderate the rate and severity of climate change by absorbing massive amounts of anthropogenic CO2 but this results in large-scale changes in seawater chemistry, which are collectively referred to as anthropogenic ocean acidification. Despite its potentially widespread consequences, the problem of ocean acidification has been largely absent from most policy discussions of CO2 emissions, both because the science is relatively new and because the research community has yet to deliver a clear message to decision makers regarding its impacts. Here we report the results of the first expert survey in the field of ocean acidification. Fifty-three experts, who had previously participated in an IPCC workshop, were asked to assess 22 declarative statements about ocean acidification and its consequences. We find a relatively strong consensus on most issues related to past, present and future chemical aspects of ocean acidification: non-anthropogenic ocean acidification events have occurred in the geological past, anthropogenic CO2 emissions are the main (but not the only) mechanism generating the current ocean acidification event, and anthropogenic ocean acidification that has occurred due to historical fossil fuel emissions will be felt for centuries. Experts generally agreed that there will be impacts on biological and ecological processes and biogeochemical feedbacks but levels of agreement were lower, with more variability across responses. Levels of agreement were higher for statements regarding calcification, primary production and nitrogen fixation than for those about impacts on foodwebs. The levels of agreement for statements pertaining to socio-economic impacts, such as impacts on food security, and to more normative policy issues, were relatively low.
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Changing Frequency of Heavy Rainfall over the Central United States
Gabriele Villarini, James Smith & Gabriel Vecchi
Journal of Climate, January 2013, Pages 351-357
Abstract:
Records of daily rainfall accumulations from 447 rain gauge stations over the central United States (Minnesota, Wisconsin, Michigan, Iowa, Illinois, Indiana, Missouri, Kentucky, Tennessee, Arkansas, Louisiana, Alabama, and Mississippi) are used to assess past changes in the frequency of heavy rainfall. Each station has a record of at least 50 yr, and the data cover most of the twentieth century and the first decade of the twenty-first century. Analyses are performed using a peaks-over-threshold approach, and, for each station, the 95th percentile is used as the threshold. Because of the count nature of the data and to account for both abrupt and slowly varying changes in the heavy rainfall distribution, a segmented regression is used to detect changepoints at unknown points in time. The presence of trends is assessed by means of a Poisson regression model to examine whether the rate of occurrence parameter is a linear function of time (by means of a logarithmic link function). The results point to increasing trends in heavy rainfall over the northern part of the study domain. Examination of the surface temperature record suggests that these increasing trends occur over the area with the largest increasing trends in temperature and, consequently, with an increase in atmospheric water vapor.
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Response of snow-dependent hydrologic extremes to continued global warming
Noah Diffenbaugh, Martin Scherer & Moetasim Ashfaq
Nature Climate Change, April 2013, Pages 379-384
Abstract:
Snow accumulation is critical for water availability in the Northern Hemisphere, raising concern that global warming could have important impacts on natural and human systems in snow-dependent regions. Although regional hydrologic changes have been observed, the time of emergence of extreme changes in snow accumulation and melt remains a key unknown for assessing climate-change impacts. We find that the CMIP5 global climate model ensemble exhibits an imminent shift towards low snow years in the Northern Hemisphere, with areas of western North America, northeastern Europe and the Greater Himalaya showing the strongest emergence during the near-term decades and at 2 °C global warming. The occurrence of extremely low snow years becomes widespread by the late twenty-first century, as do the occurrences of extremely high early-season snowmelt and runoff (implying increasing flood risk), and extremely low late-season snowmelt and runoff (implying increasing water stress). Our results suggest that many snow-dependent regions of the Northern Hemisphere are likely to experience increasing stress from low snow years within the next three decades, and from extreme changes in snow-dominated water resources if global warming exceeds 2 °C above the pre-industrial baseline.
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Funding Global Public Goods: The Dark Side of Multilateralism
Patrick Bayer & Johannes Urpelainen
Review of Policy Research, March 2013, Pages 160-189
Abstract:
The funding of global public goods, such as climate mitigation, presents a complex strategic problem. Potential recipients demand side payments for implementing projects that furnish global public goods, and donors can cooperate to provide the funding. We offer a game-theoretic analysis of this problem. In our model, a recipient demands project funding. Donors can form a multilateral program to jointly fund the project. If no program is formed, bilateral funding remains a possibility. We find that donors rely on multilateralism if their preferences are relatively symmetric and domestic political constraints on funding are lax. In this case, the recipient secures large rents from project implementation. Thus, even donors with strong interests in global public good provision have incentives to oppose institutional arrangements that promote multilateral funding. These incentives have played an important role in multilateral negotiations on climate finance, especially in Cancun (2010) and Durban (2011).
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Evolutionary change during experimental ocean acidification
Melissa Pespeni et al.
Proceedings of the National Academy of Sciences, forthcoming
Abstract:
Rising atmospheric carbon dioxide (CO2) conditions are driving unprecedented changes in seawater chemistry, resulting in reduced pH and carbonate ion concentrations in the Earth's oceans. This ocean acidification has negative but variable impacts on individual performance in many marine species. However, little is known about the adaptive capacity of species to respond to an acidified ocean, and, as a result, predictions regarding future ecosystem responses remain incomplete. Here we demonstrate that ocean acidification generates striking patterns of genome-wide selection in purple sea urchins (Strongylocentrotus purpuratus) cultured under different CO2 levels. We examined genetic change at 19,493 loci in larvae from seven adult populations cultured under realistic future CO2 levels. Although larval development and morphology showed little response to elevated CO2, we found substantial allelic change in 40 functional classes of proteins involving hundreds of loci. Pronounced genetic changes, including excess amino acid replacements, were detected in all populations and occurred in genes for biomineralization, lipid metabolism, and ion homeostasis - gene classes that build skeletons and interact in pH regulation. Such genetic change represents a neglected and important impact of ocean acidification that may influence populations that show few outward signs of response to acidification. Our results demonstrate the capacity for rapid evolution in the face of ocean acidification and show that standing genetic variation could be a reservoir of resilience to climate change in this coastal upwelling ecosystem. However, effective response to strong natural selection demands large population sizes and may be limited in species impacted by other environmental stressors.
Thursday, April 11, 2013
Baby bump
Financial Incentives and Fertility
Alma Cohen, Rajeev Dehejia & Dmitri Romanov
Review of Economics and Statistics, March 2013, Pages 1-20
Abstract:
Using panel data on over 300,000 Israeli women from 1999 to 2005, we exploit variation in Israel's child subsidy to identify the impact of changes in the price of a marginal child on fertility. We find a positive, statistically significant, and economically meaningful price effect on overall fertility and, consistent with Becker (1960) and Becker and Tomes (1976), a small effect of income on fertility, which is negative at low and positive at high income levels. We also find a price effect on fertility among older women, suggesting that part of the overall effect is due to a reduction in total fertility.
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The Effect of Abortion Legalization on Childbearing by Unwed Teenagers in Future Cohorts
Serkan Ozbeklik
Economic Inquiry, forthcoming
Abstract:
This article examines the long-term impact of legalized abortion on childbearing by unwed teenagers in the United States. I find that the 1970 legalization of abortion in the repeal states led to about a 6% reduction in unwed childbearing rates for white women aged 15-20 who were born in these states immediately after abortion became legal. I find a larger long-term impact for African-American women of the same ages: a 7.5%-13% reduction in unwed childbearing. My estimates are smaller and not as precise for the effect of Roe v. Wade. This outcome is not surprising given that I am able to estimate only a potential lower bound of the effect on unwed childbearing rates. On the other hand, when I estimated a Difference-in-Difference regression for the non-repeal states assuming that there was no national trend that affected the childbearing behavior of the treatment age groups and their respective control age groups separately, I found that the true effect of Roe v. Wade on childbearing by unwed teenagers was about an 11% and 3% reductions for white and African-American teenagers, respectively.
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New Cohort Fertility Forecasts for the Developed World: Rises, Falls, and Reversals
Mikko Myrskylä, Joshua Goldstein & Yen-hsin Alice Cheng
Population and Development Review, March 2013, Pages 31-56
Abstract:
With period fertility having risen in many low-fertility countries, an important emerging question is whether cohort fertility trends are also reversing. We produce new estimates of cohort fertility for 37 developed countries using a new, simple method that avoids the underestimation typical of previous approaches. Consistent with the idea that timing changes were largely responsible for the last decades' low period fertility, we find that family size has remained considerably higher than the period rates of 1.5 in many "low-fertility" countries, averaging about 1.8 children. Our forecasts suggest that the long-term decline in cohort fertility is flattening or reversing in many world regions previously characterized by low fertility. We document the marked increase of cohort fertility in the English-speaking world and in Scandinavia; signs of an upward reversal in many low-fertility countries, including Japan and Germany; and continued declines in countries such as Taiwan and Portugal. We include in our forecasts estimates of statistical uncertainty and the possible effects of the recent economic recession.
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Reyn van Ewijk, Rebecca Painter & Tessa Roseboom
American Journal of Epidemiology, forthcoming
Abstract:
A growing body of evidence suggests that maternal diet during pregnancy can lead to permanent alterations to the physiology of the fetus. It is unknown whether intermittent maternal fasting during Ramadan has long-term associations with the offspring's body composition. By using data from the third wave of the Indonesian Family Life Survey (2000), we compared the body mass indices (weight (kg)/height (m)2) of Muslims who had been in utero during Ramadan with those of Muslims who had not been in utero during Ramadan. Adult Muslims who had been in utero during Ramadan were slightly thinner than Muslims who had not been in utero during Ramadan (adjusted adult body mass index: -0.32, 95% confidence interval: -0.57, -0.06). Those who were conceived during Ramadan also had smaller stature, being on average 0.80 cm shorter than those who were not exposed to Ramadan prenatally. Among non-Muslims, no such associations were found. This study suggests that exposure to Ramadan during pregnancy may have lasting consequences for adult body size of the offspring.
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Arindam Nandi & Anil Deolalikar
Journal of Development Economics, July 2013, Pages 216-228
Abstract:
Despite strong recent economic growth, gender inequality remains a major concern for India. This paper examines the effectiveness of a public policy geared towards the reduction of gender inequality. The national Pre-Conception and Pre-Natal Diagnostics Techniques (PNDT) Act of 1994, implemented in 1996, banned sex-selective abortions in India. Although demographers frequently mention the futility of the Act, we are among the first to evaluate the law using a treatment-effect analysis framework. Using village and town level longitudinal data from the 1991 and 2001 censuses, we find a significantly positive impact of the PNDT Act on female-to-male child sex ratio. Given the almost ubiquitous decline in the observed child sex ratio during this period, we argue that the law was successful in preventing any further worsening of the gender imbalance. We find that a possible absence of the law would have led to at least 106,000 fewer female children.
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Thomas Pollet, Kelly Cobey & Leander van der Meij
PLoS ONE, April 2013
Abstract:
Variation in testosterone (T) is thought to affect the allocation of effort between reproductive and parenting strategies. Here, using a large sample of elderly American men (n = 754) and women (n = 669) we examined the relationship between T and self-reported parenthood, as well as the relationship between T and number of reported children. Results supported previous findings from the literature, showing that fathers had lower T levels than men who report no children. Furthermore, we found that among fathers T levels were positively associated with the number of children a man reports close to the end of his lifespan. Results were maintained when controlling for a number of relevant factors such as time of T sampling, participant age, educational attainment, BMI, marital status and reported number of sex partners. In contrast, T was not associated with either motherhood or the number of children women had, suggesting that, at least in this sample, T does not influence the allocation of effort between reproductive and parenting strategies among women. Findings from this study contribute to the growing body of literature suggesting that, among men, pair bonding and paternal care are associated with lower T levels, while searching and acquiring sex partners is associated with higher T levels.
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Contraceptive use and unmet need for family planning in Iran
Mohammad Motlaq et al.
International Journal of Gynecology & Obstetrics, May 2013, Pages 157-161
Objective: To determine the prevalence of contraceptive use and unmet need for family planning in Iran and to explore the public-health implications.
Methods: A nationwide cross-sectional study was conducted by interviewing 2120 married women aged 15-49 years. The sample population was enrolled in 6 large Iranian cities (Tehran, Mashhad, Tabriz, Isfahan, Shiraz, and Ahvaz) and 2 small cities (Zahedan and Kerman) from September 22 to December 20, 2011.
Results: The overall contraceptive prevalence rate was 81.5% and the unmet need for any method of contraception was 2.6% (95% confidence interval, 2.0%-3.3%). Given the frequency of women who used traditional contraceptive methods (22.3%), the unmet need for modern methods was estimated as 17.4%. The main reasons given for unmet need for family planning were low perceived risk of pregnancy (41.8%) and family opposition (21.8%). Unwanted pregnancy was reported by 30.7% of the participants.
Conclusion: A high rate of unmet need for modern contraceptive methods might potentially lead to increased rates of unwanted pregnancies and induced abortions. Healthcare policymakers should, therefore, be warned against a sense of complacency that family planning in Iran does not need their support.
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Douglas Almond, Lena Edlund & Kevin Milligan
Population and Development Review, March 2013, Pages 75-95
Abstract:
Preference for sons over daughters, evident in China's and South Asia's male sex ratios, is commonly rationalized by poverty and the need for old-age support. In this article we study South and East Asian immigrants to Canada, a group for whom the economic imperative to select sons is largely absent. Analyzing the 2001 and 2006 censuses, 20 percent samples, we find clear evidence of extensive sex selection in favor of boys at higher parities among South and East Asian immigrants unless they are Christian or Muslim. The latter finding accords with the explicit prohibition against (female) infanticide - traditionally the main sex-selection method - in these religions. Our findings point to a strong cultural component to both the preference for sons and the willingness to resort to induced abortion based on sex.
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Autism Risk Across Generations: A Population-Based Study of Advancing Grandpaternal and Paternal Age
Emma Frans et al.
JAMA Psychiatry, forthcoming
Objective: To further expand knowledge about the association between paternal age and autism by studying the effect of grandfathers' age on childhood autism.
Design: Population-based, multigenerational, case-control study.
Setting: Nationwide multigeneration and patient registers in Sweden.
Participants: We conducted a study of individuals born in Sweden since 1932. Parental age at birth was obtained for more than 90% of the cohort. Grandparental age at the time of birth of the parent was obtained for a smaller subset (5936 cases and 30 923 controls).
Main Outcome and Measure: International Classification of Diseases diagnosis of childhood autism in the patient registry.
Results: A statistically significant monotonic association was found between advancing grandpaternal age at the time of birth of the parent and risk of autism in grandchildren. Men who had fathered a daughter when they were 50 years or older were 1.79 times (95% CI, 1.35-2.37; P < .001) more likely to have a grandchild with autism, and men who had fathered a son when they were 50 years or older were 1.67 times (95% CI, 1.35-2.37; P < .001) more likely to have a grandchild with autism, compared with men who had fathered children when they were 20 to 24 years old, after controlling for birth year and sex of the child, age of the spouse, family history of psychiatric disorders, highest family educational level, and residential county. A statistically significant monotonic association was also found between advancing paternal age and risk of autism in the offspring. Sensitivity analyses indicated that these findings were not the result of bias due to missing data on grandparental age.
Conclusions and Relevance: Advanced grandparental age was associated with increased risk of autism, suggesting that risk of autism could develop over generations. The results are consistent with mutations and/or epigenetic alterations associated with advancing paternal age.
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Tim Savage et al.
PLoS ONE, March 2013
Background: Maternal age at childbirth continues to increase worldwide. We aimed to assess whether increasing maternal age is associated with changes in childhood height, body composition, and metabolism.
Methods: 277 healthy pre-pubertal children, born 37-41 weeks gestation were studied. Assessments included: height and weight corrected for parental measurements, DEXA-derived body composition, fasting lipids, glucose, insulin, and hormonal profiles. Subjects were separated according to maternal age at childbirth: <30, 30-35, and >35 years.
Results: Our cohort consisted of 126 girls and 151 boys, aged 7.4±2.2 years (range 3-10); maternal age at childbirth was 33.3±4.7 years (range 19-44). Children of mothers aged >35 and 30-35 years at childbirth were taller than children of mothers aged <30 years by 0.26 (p = 0.002) and 0.23 (p = 0.042) SDS, respectively. There was a reduction in childhood BMISDS with increasing maternal age at childbirth, and children of mothers aged >35 years at childbirth were 0.61 SDS slimmer than those of mothers <30 years (p = 0.049). Children of mothers aged 30-35 (p = 0.022) and >35 (p = 0.036) years at childbirth had abdominal adiposity reduced by 10% and 13%, respectively, compared to those in the <30 group. Children of mothers aged 30-35 years at childbirth displayed a 19% increase in IGF-I concentrations compared to offspring in <30 group (p = 0.042). Conversely, IGF-II concentrations were lower among the children born to mothers aged 30-35 (6.5%; p = 0.004) and >35 (8.1%; p = 0.005) compared to those of mothers aged <30 years. Girls of mothers aged 30-35 years at childbirth also displayed improved HOMA-IR insulin sensitivity (p = 0.010) compared to girls born to mothers aged <30 years.
Conclusions: Increasing maternal age at childbirth is associated with a more favourable phenotype (taller stature and reduced abdominal fat) in their children, as well as improved insulin sensitivity in girls.
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Roland Pongou
Demography, April 2013, Pages 421-444
Abstract:
Infant mortality is higher in boys than girls in most parts of the world. This has been explained by sex differences in genetic and biological makeup, with boys being biologically weaker and more susceptible to diseases and premature death. At the same time, recent studies have found that numerous preconception or prenatal environmental factors affect the probability of a baby being conceived male or female. I propose that these environmental factors also explain sex differences in mortality. I contribute a new methodology of distinguishing between child biology and preconception environment by comparing male-female differences in mortality across opposite-sex twins, same-sex twins, and all twins. Using a large sample of twins from sub-Saharan Africa, I find that both preconception environment and child biology increase the mortality of male infants, but the effect of biology is substantially smaller than the literature suggests. I also estimate the interacting effects of biology with some intrauterine and external environmental factors, including birth order within a twin pair, social status, and climate. I find that a twin is more likely to be male if he is the firstborn, born to an educated mother, or born in certain climatic conditions. Male firstborns are more likely to survive than female firstborns, but only during the neonatal period. Finally, mortality is not affected by the interactions between biology and climate or between biology and social status.
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Geographical Mobility and Reproductive Choices of Italian Men
Raffaele Guetto & Nazareno Panichella
European Sociological Review, April 2013, Pages 302-315
Abstract:
In addition to women's increased educational attainment and institutional settings, also changed orientations toward family to achieve full life-satisfaction have been underlined to explain low fertility rates. Since Southern and Northern Italy differ for the institutional and economic setting, cultural orientations regarding the importance of family as well as fertility rates, also for Italy it seems reasonable to suppose that the latter are caused by both ‘structural' and ‘cultural' factors. We argue that South-to-North migrations could be an interpretative key of geographical differences in the timing and number of childbirths. In fact, migrants are socialized to different familiar behaviours, although they share with Northerners the same institutional and economic setting. We use data from the Italian Households Longitudinal Survey and apply event history models to Italian men's transition to parenthood. Our results show that North-South differences in the transition to the first child are largely explained by different levels and patterns of female labour market participation, while preferences could have a crucial impact in the transition to the second child, where migrants and Southerners are equally much faster than Northerners. We think that these results contribute to both the literature about fertility determinants and long-term consequences of migrations.
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The Effect of Fertility Reduction on Economic Growth
Quamrul Ashraf, David Weil & Joshua Wilde
Population and Development Review, March 2013, Pages 97-130
Abstract:
We assess quantitatively the effect of exogenous reductions in fertility on output per capita. Our simulation model allows for effects that run through schooling, the size and age structure of the population, capital accumulation, parental time input into childrearing, and crowding of fixed natural resources. The model is parameterized using a combination of microeconomic estimates and standard components of quantitative macroeconomic theory. We apply the model to examine the effect of a change in fertility from the UN medium-variant to the UN low-variant projection in Nigeria. For a base case set of parameters, we find that such a change would raise output per capita by 5.6 percent at a horizon of 20 years and by 11.9 percent at a horizon of 50 years. We conclude with a discussion of the quantitative significance of these results.
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Laure Dossus et al.
International Journal of Epidemiology, April 2013, Pages 590-600
Background: Age at menarche is an important determinant of hormonal-related neoplasia and other chronic diseases. Spatial and temporal variations in age at menarche have been observed in industrialised countries and several environmental factors were reported to have an influence.
Method: We examined geographical variations in self-reported age at menarche and explored the effects of both latitude and ultraviolet radiation (UVR) dose on the onset of menarche in 88 278 women from the French E3N cohort (aged 40-65 years at inclusion).
Results: The mean age at menarche was 12.8 years. After adjustment for potential confounders (birth cohort, prematurity, birth weight and length, father's income index, body silhouette in childhood, food deprivation during World War II, population of birthplace, number of siblings, breastfeeding exposure and indoor exposure to passive smoking during childhood), latitude and UVR dose (annual or spring/summer) in county of birth were significantly associated with age at menarche (Ptrend < 0.0001). Women born at lower latitudes or in regions with higher annual or spring/summer UVR dose had a 3- to 4-month earlier menarche than women born at higher latitudes or in regions with lower UVR. On a continuous scale, a 1° increment in latitude resulted in a 0.04-year older age at menarche [95% confidence interval (CI): 0.03, 0.05], whereas a 1-kJ/m2 increment in annual UVR dose resulted in a 0.42-year younger age at menarche (95% CI: -0.55, -0.29).
Conclusion: These data further suggest that light exposure in childhood may influence sexual maturation in women.
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The Impact of Malaria Eradication on Fertility
Adrienne Lucas
Economic Development and Cultural Change, April 2013, Pages 607-631
Abstract:
The malaria eradication campaign that started in Sri Lanka in the late 1940s virtually eliminated malaria transmission on the island. I use the preeradication differences in malaria endemicity within Sri Lanka to identify the effect of malaria eradication on fertility and child survival. Malaria eradication increased the number of live births through increasing age-specific fertility and causing an earlier first birth. The effect of malaria on the transition time to higher-order births is inconclusive. Malaria could directly or indirectly affect survival probabilities of live births. I exploit the particular epidemiology of malaria that causes more severe sequelae during an initial pregnancy. I find differential changes in survival probabilities by birth order that are most likely due to the direct in utero effects of malaria. The increase in population growth after malaria eradication reconciles the contradictory findings in the macroeconomic and microeconomic literatures: the increased productivity and education from malaria eradication will only appear in aggregate measures like GDP per capita after a delay because of the initial increase in the population size.
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Parent-Offspring Conflict and the Persistence of Pregnancy-Induced Hypertension in Modern Humans
Birgitte Hollegaard et al.
PLoS ONE, February 2013
Abstract:
Preeclampsia is a major cause of perinatal mortality and disease affecting 5-10% of all pregnancies worldwide, but its etiology remains poorly understood despite considerable research effort. Parent-offspring conflict theory suggests that such hypertensive disorders of pregnancy may have evolved through the ability of fetal genes to increase maternal blood pressure as this enhances general nutrient supply. However, such mechanisms for inducing hypertension in pregnancy would need to incur sufficient offspring health benefits to compensate for the obvious risks for maternal and fetal health towards the end of pregnancy in order to explain why these disorders have not been removed by natural selection in our hunter-gatherer ancestors. We analyzed >750,000 live births in the Danish National Patient Registry and all registered medical diagnoses for up to 30 years after birth. We show that offspring exposed to pregnancy-induced hypertension (PIH) in trimester 1 had significantly reduced overall later-life disease risks, but increased risks when PIH exposure started or developed as preeclampsia in later trimesters. Similar patterns were found for first-year mortality. These results suggest that early PIH leading to improved postpartum survival and health represents a balanced compromise between the reproductive interests of parents and offspring, whereas later onset of PIH may reflect an unbalanced parent-offspring conflict at the detriment of maternal and offspring health.
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Seminal and molecular evidence that sauna exposure affects human spermatogenesis
Andrea Garolla et al.
Human Reproduction, April 2013, Pages 877-885
Study question: What are the effects of continuous sauna exposure on seminal parameters, sperm chromatin, sperm apoptosis and expression of genes involved in heat stress and hypoxia?
Summary answer: Scrotal hyperthermia by exposure to sauna can induce a significant alteration of spermatogenesis.
Study design, size and duration: A longitudinal time-course study. Data from 10 subjects exposed to Finnish sauna were collected before sauna (T0), after3 months of sauna sessions (T1) and after 3 (T2) and 6 months (T3) from the end of sauna exposure.
Participants/materials, setting and methods: Ten normozoospermic volunteers underwent two sauna sessions per week for 3 months, at 80-90°C, each lasting 15 min. Sex hormones, sperm parameters, sperm chromatin structure, sperm apoptosis and expression of genes involved in heat stress and hypoxia were evaluated at the start, at the end of sauna exposure and after 3 and 6 months from sauna discontinuation. Student's t-test for paired data was used for statistical analysis.
Main results and the role of chance: At the end of sauna exposure, we found a strong impairment of sperm count and motility (P < 0.001), while no significant change in sex hormones was present. Decreases in the percentage of sperm with normal histone-protamine substitution (78.7 ± 4.5 versus 69.0 ± 4.1), chromatin condensation (70.7 ± 4.7 versus 63.6 ± 3.3) and mitochondrial function (76.8 ± 4.9 versus 54.0 ± 6.1) were also evident at T1, and strong parallel up-regulation of genes involved in response to heat stress and hypoxia was found. All these effects were completely reversed at T3.
Wider implications of the findings: Our data demonstrated for the first time that in normozoospermic subjects, sauna exposure induces a significant but reversible impairment of spermatogenesis, including alteration of sperm parameters, mitochondrial function and sperm DNA packaging. The large use of Finnish sauna in Nordic countries and its growing use in other parts of the world make it important to consider the impact of this lifestyle choice on men's fertility.
