Homophily, group size, and the diffusion of political information in social networks: Evidence from Twitter

We investigate the role of homophily - a tendency to interact with similar individuals-in the diffusion of political information in social networks. We develop a model predicting disproportionate exposure to like-minded information and that larger groups have more connections and are exposed to more information. To test these hypotheses, we use data on links and communications between politically-engaged Twitter users. We find that users affiliated with majority political groups, relative to the minority group, have more connections, are exposed to more information, and are exposed to information more quickly. Likewise, we find that users are disproportionately exposed to like-minded information and that information reaches like-minded users more quickly.