Comparative Statics for Aggregative Games: The Strong Concavity Case

Abstract

In this paper we study the effects of a change in some exogenous variable (the number of players or a parameter in the payoff funtions) on the strategies played an payoffs obtained in a Nash equilibrium in the framework of an Aggregative Game (a generalization of the Cournot model). We assume a strong concavity condition which implies that the best reply function of any player is decreasing in the sum of the strategies of the remaining players(i.e. strategic subtitutin). Our results generalize and unify those known in the Cournot model.