We study information acquisition in a exible framework with strategic complementarity or substitutability in actions and a rich set of externalities that are responsible for possible wedges between the equilibrium and the efficient acquisition of information. First, we relate the (in)efficiency...

This paper analyzes the situation, in which a continuum of identical players is engaged in more than one activity and each activity is characterized by a complementarity game. The player's intensity levels across different activities are linked in such a way that the marginal cost of increasing...

We study an infinitely-repeated ?rst-price auction with common values. Initially, bid- ders receive independent private signals about the objects' value, which itself does not change over time. Learning occurs only through observation of the bids. Under one-sided incomplete information, this...

Often, perfect bayesian equilibrium is loosely defined by stating that players should be sequentially rational given some beliefs in which Bayes rule is applied “whenever possible”. We show that there are games in which it is not clear what “whenever possible” means. Then, we provide a...

In the prisoners' dilemma game, the only evolutionary stable strategy is defection, even though nutual cooperation yields a higher payoff. Building on a paper by Robson (1990), we introduce mutants who have the ability to send a (costly) signal, i.e., the "secret handshake," before each round of...

We study all-pay auctions (or wars of attrition), where the highest bidder wins an object, but all bidders pay their bids. We consider such auctions when two bidders alternate in raising their bids and where all aspects of the auction are common knowledge including bidders' valuations. We...

In general, the result of the elimination of weakly dominated strategies depends on order. We define nice weak dominance. Under nice weak dominance, order does not matter. We identify an important class of games under which nice weak dominance and weak dominance are equivalent, and so order...

Contracts adopted with later renegotiation in mind may take simple forms. In a principal-agent model, if renegotiation may occur after the agent chooses efforet, the principal protects against unfavorable renegotiation by "selling the project" to the agent via a sales contract. If only singleton...

Sales contracts emerge when a principal and an agent in amoral hazard environment cannot prevent themselves from renegotiating their contract. The renegotiation occurs after the agent chooses his unobservable effort, but before its consequences are realized. Unlike previous analyses, a contract...

We examine the consequences of vote buying, assuming this practice were al- lowed and free of stigma. Two parties compete in a binary election and may purchase votes in a sequential bidding game via up-front binding payments and/or campaign promises (platforms) that are contingent upon the...