This paper studies the practice of influencer marketing in oligopoly markets and its effect on market efficiency. We develop a duopoly model in which firms sell horizontally differentiated products. Consumers are influenced by other consumers' choices, and some consumers are more influential...

Recent developments in social media have morphed the age-old practice of paying influential individuals for product endorsements into a multibillion-dollar industry, extending well beyond celebrity sponsorships. We develop a parsimonious model in which influencers trade off the increased revenue...

We consider the spread of a harmful state through a population divided into two groups. Interaction patterns capture the full spectrum of assortativity possibilities. We show that a central planner who aims for eradication optimally either divides equally the resources across groups, or...

This paper studies the effect of social learning on political outcomes in a model of informative campaign advertising. Voters' communication network affects parties' incentives to disclose political information, voters' learning about candidates running for office, and polarization of the...