In online social networks, social information, i.e., content generated and shared by users (e.g., past purchases), can be a substitute for sponsored advertising, which constitutes the network's main source of revenue. When will social information be let to spread freely over the platform? We...

We consider a strategic online social network that controls information flows between agents in a social learning setting. Agents on the network select among products of competing firms of unknown quality. The network sells advertising to firms. We consider display advertising, which is standard...