Cognitive abilities and economic behavior

At the heart of behavioral and experimental economics is the goal to better understand behavior through observation so that economic models can be improved. However, despite the predictions of classical economics, the researcher is often confronted with a great deal of behavioral heterogeneity. One way to approach this heterogeneity is to acknowledge that decision makers differ from each other in fundamental ways and these differences contribute to the differences in observed economic behavior

Experimental and self-reported measures of risk taking and digit ratio (2D:4D): evidence from a large, systematic study

Using a large (n=704) sample of laboratory subjects, we systematically investigate the links between the digit ratio - a biomarker for pre-natal testosterone exposure - and two measures of individual risk taking: (i) risk preferences over lotteries with real monetary incentives, and (ii) self-reported risk attitude. The digit ratio (also called 2D:4D) is the ratio of the length of the index finger to the length of the ring finger, and we consider both hands’ digit ratios. Previous studies have found that the digit ratio correlates with risk taking in some subject samples, but not others. In our sample, we find that both the right-hand and the left-hand digit ratio are significantly associated with risk preferences: subjects with lower digit ratios tend to choose riskier lotteries. Neither digit ratio, however, is associated with self-reported risk attitude

Second-to-fourth digit ratio has a non-monotonic impact on altruism

Gene-culture co-evolution emphasizes the joint role of culture and genes for the emergence of altruistic and cooperative behaviors and behavioral genetics provides estimates of their relative importance. However, these approaches cannot assess which biological traits determine altruism or how. We analyze the association between altruism in adults and the exposure to prenatal sex hormones, using the second-to-fourth digit ratio. We find an inverted U-shaped relation for left and right hands, which is very consistent for men and less systematic for women. Subjects with both high and low digit ratios give less than individuals with intermediate digit ratios. We repeat the exercise with the same subjects seven months later and find a similar association, even though subjects’ behavior differs the second time they play the game. We then construct proxies of the median digit ratio in the population (using more than 1000 different subjects), show that subjects’ altruism decreases with the distance of their ratio to these proxies. These results provide direct evidence that prenatal events contribute to the variation of altruistic behavior and that the exposure to fetal hormones is one of the relevant biological factors. In addition, the findings suggest that there might be an optimal level of exposure to these hormones from social perspective

The appropriate response of Spanish Gitanos: short-run orientation beyond current socio-economic status

Humans differ greatly in their tendency to discount future events, but the reasons underlying such inter-individual differences remain poorly understood. Based on the evolutionary framework of Life History Theory, influential models predict that the extent to which individuals discount the future should be influenced by socio-ecological factors such as mortality risk, environmental predictability and resource scarcity. However, little empirical work has been conducted to compare the discounting behavior of human groups facing different socio-ecological conditions. In a lab-in-the-field economic experiment, we compared the delay discounting of a sample of Romani people from Southern Spain (Gitanos) with that of their non-Romani neighbors (i.e., the majority Spanish population). The Romani-Gitano population constitutes the main ethnic minority in all of Europe today and is characterized by lower socio-economic status (SES), lower life expectancy and poorer health than the majority, along with a historical experience of discrimination and persecution. According to those Life History Theory models, Gitanos will tend to adopt “faster” life history strategies (e.g., earlier marriage and reproduction) as an adaptation to such ecological conditions and, therefore, should discount the future more heavily than the majority. Our results support this prediction, even after controlling for the individuals’ current SES (income and education). Moreover, group-level differences explain a large share of the individual-level differences. Our data suggest that human inter-group discrimination might shape group members’ time preferences through its impact on the environmental harshness and unpredictability conditions they face

Strategic behaviour in Schelling dynamics: theory and experimental evidence

In this paper we experimentally test Schelling’s (1971) segregation model and obtain the striking result of full segregation in most of the cases. In addition, we extend Schelling’s model theoretically by adding strategic behaviour and moving costs. We obtain a unique subgame perfect equilibrium in which rational agents facing moving costs may find it optimal not to move (anticipating other participants’ movements). This equilibrium is far from full segregation. We run experiments for this extended Schelling model, and find that the percentage of full segregated societies is notably reduced when the cost of moving is high, but it is not affected when it is low, relative to the baseline with costless moving. We also find that the degree of segregation depends on the distribution of strategic subjects relative of a baseline model where moving is costless

To the Rescue: Optimally Locating Trauma Hospitals and Helicopters

Injury (trauma) is the leading cause of death in the United States for people younger than 45 years of age. Each day, more than 170,000 men, women, and children are injured severely enough to seek medical care. About 400 of these people will die and another 200 will sustain a long-term disability as a result of their injuries. An estimated 20-40% of trauma-related deaths could be prevented if all Americans lived in communities that were served by a well-organized system of trauma care. This Issue Brief describes a new computer model that can help State and regional policymakers decide where to place designated trauma hospitals and helicopter depots to maximize their residents’ access to trauma care

Digit ratio (2D:4D) and social integration: an effect of prenatal sex hormones

The position people occupy in their social and professional networks is related to their social status and has strong effects on their access to social resources. While attainment of particular positions is driven by behavioral traits, many biological factors predispose individuals to certain behaviors and motivations. Prior work on exposure to fetal androgens (measured by second-to-fourth digit ratio, 2D:4D) shows that it correlates with behaviors and traits related to social status, which might make people more socially integrated. However, it also predicts certain anti-social behaviors and disorders associated with lower socialization. We explore whether 2D:4D correlates with network position later in life and find that individuals with low 2D:4D become more central in their social environment. Interestingly, low 2D:4D males are more likely to exhibit high betweenness centrality (they connect separated parts of the social structure) while low 2D:4D females are more likely to exhibit high in-degree centrality (more people name them as friends). These gender-specific differences are reinforced by transitivity (the likelihood that one’s friends are also friends with one another): neighbors of low 2D:4D men tend not to know each other; the contrary is observed for low 2D:4D women. Our results suggest that biological predispositions influence the organization of human societies and that exposure to prenatal androgens influences different status seeking behaviors in men and women

State Firearm Laws and Interstate Firearm Deaths From Homicide and Suicide in the United States: A Cross-Sectional Analysis of Data by County

In a cross-sectional analysis of deaths from 2010 through 2014, states with strong gun laws had lower rates of firearm-related homicide and suicide than states with less regulation. Counties in states with less restrictive firearms laws had relatively lower rates of firearm-related homicide when they bordered states with strict gun laws. In contrast, rates of gun violence in areas with strong gun laws were unaffected by lenient laws in neighboring states. Restrictions on the sale and ownership of firearms may have measurable effects on rates of firearm deaths, with potential spillover across state lines

Perceived Effectiveness of Acupuncture: Findings From the National Health Interview Survey

Background: Knowledge of perceived benefit from acupuncture treatment is important to predict who is using acupuncture, to inform physicians of the possible benefits of acupuncture, to determine where rigorous research should be focused, and to help policy makers predict future demand. Objectives: To determine the proportions of survey respondents who reported perceived effectiveness of acupuncture treatment for specific conditions; and to determine the association of specified demographic variables with perceived effectiveness. Design, Setting, and Participants: Publicly available data from 31,044 noninstitutionalized US adults who participated in the 2002 National Health Interview Survey, a cross-sectional in-home computer-assisted interview. Outcome Measures: The proportions of participants reporting “any help” and “great help” for perceived effectiveness across conditions treated and per condition treated; and the association of the subgroups within age, sex, and body mass index (BMI), along with the subgroups Asian race and Chinese ethnicity, with “any help” of acupuncture treatment across conditions treated. Results: Of the 1,274 respondents who reported having consulted an acupuncturist, 329 had used acupuncture in the last 12 months; 276 had used acupuncture to treat a specific condition. A total of 86% of respondents reported being helped by acupuncture, while 45% reported being greatly helped across conditions treated. In an examination of specific conditions treated, the range for “any help” was 98% to 67%, and 98% to 7% in the “great help” outcome. Older age and obesity were negatively associated with perceived effectiveness statistically but not clinically. Asian race and Chinese ethnicity were not statistically significantly associated with perceived effectiveness. Conclusions: Acupuncture is perceived to be effective by most respondents who used it to treat a specific condition. Older age and obesity are negatively associated with perceived effectiveness, but not at a clinically significant level. A larger sample of Asian and Chinese subgroups is needed to determine if there is an association of these subgroups with perceived benefit

Sex Differences in rt-PA Utilization at Hospitals Treating Stroke: The National Inpatient Sample.

BACKGROUND AND PURPOSE: Sex and race disparities in recombinant tissue plasminogen activator (rt-PA) use have been reported. We sought to explore sex and race differences in the utilization of rt-PA at primary stroke centers (PSCs) compared to non-PSCs across the US. METHODS: Data from the National (Nationwide) Inpatient Sample (NIS) 2004-2010 was utilized to assess sex differences in treatment for ischemic stroke in PSCs compared to non-PSCs. RESULTS: There were 304,152 hospitalizations with a primary diagnosis of ischemic stroke between 2004 and 2010 in the analysis: 75,160 (24.7%) patients were evaluated at a PSC. A little over half of the patients evaluated at PSCs were female (53.8%). A lower proportion of women than men received rt-PA at both PSCs (6.8 vs. 7.5%, p \u3c 0.001) and non-PSCs (2.3 vs. 2.8%, p \u3c 0.001). After adjustment for potential confounders the odds of being treated with rt-PA remained lower for women regardless of presentation to a PSC (OR 0.87, 95% CI 0.81-0.94) or non-PSC (OR 0.88, 95% CI 0.82-0.94). After stratifying by sex and race, the lowest absolute treatment rates were observed in black women (4.4% at PSC, 1.9% at non-PSC). The odds of treatment, relative to white men, was however lowest for white women (PSC OR = 0.85, 95% CI 0.78-0.93; non-PSC OR = 0.80, 95% CI 0.75-0.85). In the multivariable model, sex did not modify the effect of PSC certification on rt-PA utilization (p-value for interaction = 0.58). CONCLUSION: Women are less likely to receive rt-PA than men at both PSCs and non-PSCs. Absolute treatment rates are lowest in black women, although the relative difference in men and women was greatest for white women