Party activists wish to (i) advocate the best policy and yet (ii) unify behind a commonparty line. An activist's understanding of his environment is based on the speeches ofparty leaders. A leader's influence, measured by the weight placed on her speech,increases with her judgement on policy...

In a plurality-rule election, a group of voters must coordinate behind one of two challengers in order to defeat a disliked status quo. Departing from existing work, the support for each challenger must be inferred from the private observation of informative signals. The unique equilibrium...

We propose a framework for analyzing transformations of demand. Such transformations frequently stem from changes in the dispersion of consumers' valuations, which lead to rotations of the demand curve. In many settings, profits are a U-shaped function of dispersion. High dispersion is...

Firms selling multiple quality-differentiated products frequently alter their product lines when a competitor enters the market. We present a model of multiproduct monopoly and duopoly using a general "upgrades" approach that yields a powerful analytical framework. We provide an explanation for...