Anthropology is biased toward the WEIRD -- Western, Educated, Industrialized, Rich, and Democratic societies (and in particular, to undergraduates at the University of Chicago). The paper is "The weirdest people in the world?" Behavioral and Brain Sciences (2010), 33: 61-83 Cambridge University Press. Find it here.
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 obvious a priori grounds 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 of human nature 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.
We have organized our presen- tation into a series of telescoping contrasts showing, at each level of contrast, how WEIRD people measure up relative to the available reference populations. Our first contrast compares people from modern industrialized societies with those from small-scale societies. Our second telescoping stage contrasts people from Western societies with those from non-Western industrialized societies. Next, we contrast Americans with people from other Western societies. Finally, we contrast university- educated Americans with non – university-educated Amer- icans, or university students with non-student adults, depending on the available data. At each level we discuss behavioral and psychological phenomena for which there are available comparative data, and we assess how WEIRD people compare with other samples.
1. Comparative projects involving visual illusions, social motivations (fairness), folkbiological cogni- tion, and spatial cognition all show industrialized popu- lations as outliers. (p. 69)2. Although robust patterns have emerged among people from industrialized societies, Westerners emerge as unusual – frequent global outliers – on several key dimensions [including cooperation, anti-social punishment, self-concept, holistic-versus-analytic thinking, and moral reasoning]. (p.72)3. American participants are exceptional even within the unusual popu- lation of Westerners [for example, in their individualism and attitude toward death]. (p. 76)4. There are differences among typical subjects and the rest of the American popu- lation in unexpected domains. In some of these domains (e.g., individualism, moral reasoning, worldview defense in response to death thoughts, and perceptions of choice), the data from American undergraduates rep- resent even more dramatic departures from the patterns identified in non-Western samples. Further, contempor- ary American college students appear further removed along some of these dimensions than did their predeces- sors a few decades earlier. Typical subjects may be outliers within an outlier population. (p. 78)
And the conclusion:
The empirical foundation of the behavioral sciences comes principally from experiments with American undergraduates. The patterns we have identified in the available (albeit limited) data indicate that this sub-subpopulation is highly unusual along many important psychological and behavioral dimensions. It is not merely that researchers frequently make generalizations from a narrow subpopu- lation. The concern is that this particular subpopulation is highly unrepresentative of the species. (p. 62)
The array of responses to this target article is telling. One suggests looking for genetic similarities to explain the WEIRD results, another suggests using the internet to increase sample diversity in the "convenience sample". Several papers amplify the worry in various ways, one by extending it to allied fields like neuroscience (i.e., WEIRD people have WEIRD brains), another by linking WEIRD-based findings to normative expectations "such as might be held by international criminal tribunals in “cognitively distant” war-torn areas" (p. 98), and still another suggesting that institutionalized chimpanzees badly misrepresent wild chimpanzee populations. A contrarian suggests that WEIRD people may be the best representatives of human nature, another says the problem isn't so much the WEIRD subjects as the WEIRD researchers. A few responses seem only tenuously linked to the target article: one discusses development as a mediator between evolution and culture, another decries the use of artificial situations in behavioural research. The last response is by a philosopher, who observes that most philosophers are WEIRD men, which means philosophers' intuitions may be quite different from everyone else's.
See also here for some nice commentary by Greg Downey, especially on the descriptor "WEIRD".
From the perspective of my admittedly non-academic Brazilian colleague, the truly outstanding characteristics of the US students were characteristics like their body types, the diminishing of gender markers, and the evidence of extraordinary peer-group conformity in bearing, expression and personal presentation. His observations are hardly scientific, but they suggest that focusing on ‘Western-ness’, education, economic system, wealth, and political system certainly doesn’t exhaust the parameters of difference and it might not even highlight the most salient, although it does correspond to patterns of the Big Variables in Western scholarship about difference (when I was in grad school, it was the Holy Trinity: gender, class and ethnicity).WEIRD people are fat and sedentary, and the difference may begin in childhood, with the development of basic motor skills.