We examine a “Rotten Kid” model (Becker 1974) where a player with social preferences interacts with an egoistic player. We assume that social preferences are intentionbased rather than outcome-based. In a very general multi-stage setting we show that any equilibrium must involve mutually...

We study the effect of strengthening CACs in a debt rollover model of a sovereign debt crisis. Conditional on default, there are multiple equilibria: the impact of strengthening CACs depends critically on the prevailing equilibrium. For a subset of equilibria, (i) given a fixed number of...

Mitigation and adaptation are the most important strategies in combating global climate change. It is expected that in a post Kyoto world industrialized countries have to engage in greenhouse gas abatement, and to support developing countries in adapting to climate change. Within the framework...

We show that a cooperative outcome — one that is at least next-best for the players — is not a Nash equilibrium (NE) in 19 of the 57 2 x 2 strict ordinal conflict games (33%), including Prisoners’ Dilemma and Chicken. Auspiciously, in 16 of these games (84%), cooperative outcomes are...

Motivated by recent examples of collective effort on the war on terror, we examine the incentives that retaliation may produce for the endogenous formation of an international counterterror coalition. We show that there are quite reasonable circumstances under which any nation that is a target...

Schelling (1969, 1971a,b, 1978) considered a simple proximity model of segregation where individual agents only care about the types of people living in their own local geographical neighborhood, the spatial structure being represented by one- or two-dimensional lattices. In this paper, we argue...

Many conditions have been introduced to weaken the continuity re-quirements for equilibrium existence in games. We introduce a new con-dition, called regularity, that is simple and easy to verify. It is implied both by Reny's better-reply security and Simon and Zame's endogenous sharing rule...

We consider the regret matching process with finite memory. For general games in normal form, it is shown that any recurrent class of the dynamics must be such that the action profiles that appear in it constitute a closed set under the “same or better reply” correspondence (CUSOBR set) that...

In contexts in which players have no priors, we analyze a learning process based on ex-post regret as a guide to understand how to play games of incomplete information under private values. The conclusions depend on whether players interact within a fixed set (fixed matching) or they are...

It is well known that the rock-paper-scissors game has no pure saddle point. We show that this holds more generally: A symmetric two-player zero-sum game has a pure saddle point if and only if it is not a generalized rock-paper-scissors game. Moreover, we show that every finite symmetric...