Homophily and the Persistence of Disagreement
研究了一个态度形成动态模型，个体通过平均他人态度形成自己的态度，发现当存在一个最显著的属性时，个体最终只与相似者互动，导致分歧持续存在。
We study a dynamic model of attitude formation in which individuals average others' attitudes to develop their own. We assume that individuals exhibit homophily in sociodemographic exogenous attributes, that is, the attention they pay to each other is based on whether they possess similar attributes. We also assume that individuals exhibit homophily in attitudes, at the group level. Specifically, attributes that are salient, that is, that exhibit a substantial difference in attitudes between the groups of individuals possessing and lacking them, deserve high attention. Since we allow attention to evolve over time we prove that when there is, initially, a unique most salient attribute, it deserves growing attention overtime in detriment of the remaining ones. As a result, individuals eventually interact only with others similar to them across this attribute and disagreement persists. It materializes in two groups of thinking defined according to this attribute.