Behavioral scientists routinely publish broad claims about human psychology and behavior in the world's top journals based on samples drawn entirely from Western, Educated, Industrialized, Rich, and Democratic (WEIRD) societies. Researchers – often implicitly – assume that either there is little variation across human populations, or that these “standard subjects” are as representative of the species as any other population. Are these assumptions justified? Here, our review of the comparative database from across the behavioral sciences suggests both that there is (...) substantial variability in experimental results across populations and that WEIRD subjects are particularly unusual compared with the rest of the species – frequent outliers. The domains reviewed include visual perception, fairness, cooperation, spatial reasoning, categorization and inferential induction, moral reasoning, reasoning styles, self-concepts and related motivations, and the heritability of IQ. The findings suggest that members of WEIRD societies, including young children, are among the least representative populations one could find for generalizing about humans. Many of these findings involve domains that are associated with fundamental aspects of psychology, motivation, and behavior – hence, there are no obviousa priorigrounds for claiming that a particular behavioral phenomenon is universal based on sampling from a single subpopulation. Overall, these empirical patterns suggests that we need to be less cavalier in addressing questions ofhumannature on the basis of data drawn from this particularly thin, and rather unusual, slice of humanity. We close by proposing ways to structurally re-organize the behavioral sciences to best tackle these challenges. (shrink)

Unrealistic optimism is a bias that leads people to believe, with respect to a specific event or hazard, that they are more likely to experience positive outcomes and/or less likely to experience negative outcomes than similar others. The phenomenon has been seen in a range of health-related contexts—including when prospective participants are presented with the risks and benefits of participating in a clinical trial. In order to test for the prevalence of unrealistic optimism among participants of early-phase oncology trials, we (...) conducted a survey with patients over 18 years of age who were enrolled in a phase I, phase I/II, or phase II clinical cancer trial in the New York City area between August 2008 and October 2009. Participants in our study were asked to compare their own chances of experiencing a range of risks and benefits related to the trial they were enrolled in with the chances of the other trial participants. We found a significant optimistic bias in their responses. Respondents tended to overestimate the benefits of the trial they were enrolled in and underestimate its risks. In addition, we found no significant relationship between respondents’ understanding of the trial’s purpose and how susceptible they were to unrealistic optimism. Our findings suggest that improving the consent process for oncology studies requires more than addressing deficits in understanding. (shrink)