Homophily and the Persistence of Disagreement

This article studies the persistence of disagreement using a dynamic model in which individuals update their attitudes by averaging those of others with whom they relate. Individuals establish homophilous relations and thus favour others with similar (dichotomous) attributes. Attributes determine the intensity of relations to the extent to which there is a substantial difference in attitudes between the two groups of individuals possessing and lacking them. The main finding is that disagreement, which materialises in two different groups of thinking, persists if and only if individuals develop sufficiently intense relations over time with others similar in one specific attribute. Relations with dissimilar others deteriorate and thus these two groups emerge.