Interethnic relations, informal trading networks, and social integration: imitation, habits, and social evolution

The ethnically homogeneous middleman groups (EHMGs), which are informal trading networks, are ubiquitous in less-developed economies where the legal infrastructure for contract enforcement is not well developed. This paper develops a formal model of social interaction among members of the EHMG as well as in more general situations in a multi-ethnic or multi-cultural society consisting of identifiable ethnic or linguistic groups. Behavioral patterns are transmitted between generations and altered via imitation in social contacts. The model demonstrates how different discriminatory behavioral patterns can evolve and persist over time. One result is that the trust between such groups can increase due to a higher frequency of inter-group contacts. In concluding the paper, we speculate about how the model can be expanded to include changes in legal structures, especially contract law. This could lead to an increase in the trust between the different groups. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.