Noncooperative Game in Cooperation: Reformulation of Correlated Equilibria (II)

Abstract

In our previous paper (Kono 2008) , we introduced two essentially different concepts of correlated equilibria: one is an “exogenous correlated equilibrium relative to Z” of a noncooperative game with a mediator and the other one is an “endogenous correlated equilibrium.” In this paper, we will generalize the former to an “exogenous correlated equilibrium relative to Z1 and Z2” of a noncooperative game with agents. Under the newly defined framework, we will show that the example given in Fudenberg and Tirole (1991, p. 54) is indeed an equilibrium in the sense of Definition 2 of this paper. We will also investigate Aumann's (1974) examples that were not discussed in the previous paper. We will show some other strategy profiles that are correlated equilibria as per our paper but not found in previous works including Aumann (1974) and Fudenberg and Tirole (1991) .