Groupy versus Non-Groupy Social Preferences: Personality, Region, and Political Party†

On the sandlot and on the battlefield, people divide into groups and fight, for bragging rights and for resources. Disputes are often between groups explicitly defined as different in terms of characteristics, values, and principles. A long social psychology tradition emphasizes such group differences as the source of conflict and bias.1 Yet, new experimental research indicates that a key explanatory for group-based bias could be individual propensities, rather than the history or nature of the social division per se. In Kranton et al. (2016), participants in a university subject pool are divided into groups and allocate income to themselves and to others. The main finding is that across group treatments, some people are “groupy,” adopting different social preferences toward those who are not in their group, but many participants are “nongroupy,” showing no such bias.2 Moreover, there is a correlation with behavior outside the lab: