An influential body of psychological and anthropological theories holds that societies exhibit heterogeneous cooperation systems that differ both in their level of in-group favoritism and in the tools that they employ to enforce cooperative behavior. According to some of these theories, entire...

In this article, we analyze whether non-native speakers in the classroom affect the educational achievement and social integration of migrant and native students. In contrast to previous studies, which mainly examine the effect of the share of immigrant pupils, we focus on language heterogeneity...

Cultural psychologists and anthropologists argue that societies have developed heterogeneous systems of social organization to cope with social dilemmas, and that an entire bundle of psychological and biological characteristics has coevolved to enforce cooperation within these different regimes....