News Posting by Strategic Users in a Social Network

We argue that users in social networks are strategic in how they post and propagate information. We propose two models -- greedy and courteous -- and study information propagation both analytically and through simulations. For a suitable random graph model of a social network, we prove that news propagation follows a threshold phenomenon, hence, "high-quality" information provably spreads throughout the network assuming users are "greedy". Starting from a sample of the Twitter graph, we show through simulations that the threshold phenomenon is exhibited by both the greedy and courteous user models.