Homophily in Social Media and News Polarization

Résumé

We consider an ad-financed media firm that chooses the ideological location of its news and targets consumers who can share the news with their followers on online social media. After studying how a targeted consumer's incentive to share the news is shaped by the network structure of her followers, we study the firm's strategy to maximize the breadth of news sharing and find that when the mean (respectively, the variance) of followers' ideological locations is a convex (respectively, concave) function of a direct consumer's location, the firm is likely to produce polarized news.