The authors investigate the implementation of social choice functions that map to lotteries over alternatives. They require virtual implementation in iteratively undominated strategies. Under very weak domain restrictions, they show that if there are three or more players, any social choice...

The authors examine discounted repeated games where players privately observe different signals. A leading example is secret price cutting; a firm cannot directly observe rival firms' price cutting but its own sales can imperfectly indicate what is going on. The characterization of equilibria in...

We investigate two-player infinitely repeated games where the discount factor is less than but close to unity. Monitoring is private and players cannot communicate. We require no condition concerning the accuracy of players' monitoring technology. We show the folk theorem for the prisoners'...

Consider a two-person intertemporal bargaining problem in which players choose actions and offers each period, and collect payoffs (as a function of that period's actions) while bargaining proceeds. This can alternatively be viewed as an infinitely repeated game wherein players can offer one...

In a repeated partnership game with imperfect monitoring, the authors distinguish among the effects of (1) reducing the interest rate, (2) shortening the period over which actions are held fixed, and (3) shortening the lag with which accumulated information is reported. All three changes are...

This paper presents a systematic framework for studying infinitely-repeated games with discounting, focusing on pure strategy (subgame) perfect equilibria. It introduces a number of concepts whi ch organize the theory in a natural way. These include the idea of an optimal penal code, and the...

Consider a social choice correspondence as a mapping from preference profiles to lotteries over some finite set of alternatives. A virtually implementable social choice function in Nash equilibrium is defined, under mild domain restrictions it is shown that in societies with at least three...

A complete information bargaining model is amended to accommodate "irrational types" who are inflexible in their offers and demands. An "independence of procedures" result is derived: the bargaining outcome is independent of the details of the bargaining protocol if players can make offers...

The authors study the Nash equilibria of a two-person, infinitely-repeated game in which players' preferences depend on repeated game payoffs and the complexity of the strategies they use. The model considered is that of A. Rubinstein (1986). Necessary conditions on the structure of the...