When a news platform such as Google News or Apple News selects personalized news for its user, will it select news that conforms to its user's bias, thus creating an “echo chamber”? To answer this question, this paper studies a game between a click-maximizing platform and a rational user who...

Consider a two-player discounted infinitely repeated game. A player's belief is a probability distribution over the opponent's repeated game strategies. This paper shows that, for a large class of repeated games, there are no beliefs that satisfy three conditions, learnability, consistency, and...

Consider a two-player discounted infinitely repeated game. A player's belief is a probability distribution over the opponent's repeated game strategies. This paper shows that, for a large class of repeated games, there are no beliefs that satisfy three conditions, learnability, consistency, and...

A long-standing goal of the theory of learning in games has been to establish that rational learning leads to equilibrium. In particular, one wishes to show that as a game is played repeatedly, optimizing players learn via Bayesian updating to predict their opponents' behavior and that therefore...

Consider a two-player discounted infinitely repeated game. A player's belief is a probability distribution over the opponent's repeated game strategies. This paper shows that, for a large class of repeated games, there are no beliefs that satisfy three properties: learnability, a diversity of...