The Nash equilibrium concept combines two fundamental ideas. First, rational players choose the most preferred strategy given their beliefs about what other players will do. Second, it imposes the consistency condition that all players' beliefs are correct. This consistency condition has often...

Previous literature shows that, in many different models, limits of equilibria of perturbed games are equilibria of the unperturbed game when the sequence of perturbed games converges to the unperturbed one in an appropriate sense. The question of whether such a limit property extends to the...

In Hart and Kurz (1983), stability and formation of coalition structures has been investigated in a noncooperative framework in which the strategy of each player is the coalition he wishes to join. However, given a strategy profile, the coalition structure formed is not unequivocally determined....

Different solution concepts for strategic form games have been introduced in order to weaken the consistency assumption that players' beliefs - about their opponents strategic choices - are correct in equilibrium. The literature has shown that ambiguous beliefs are an appropriate device to deal...

In previous papers we studied a game model in which players' uncertainty is expressed entirely in the space of probabilities (lotteries) over consequences, it depends on the entire strategy profile chosen by the agents and it is described by the so called ambiguous beliefs correspondences. In...

The performance to a collective task may require a certain degree of cooperation among agents. Is cooperation viable in the sense that individual needs are fulfilled, compromises are possible and the task is performed? A model of cooperation is presented in which compromises are also ruled by...

Previous literature shows that, in many different models, limits of equilibria of perturbed games are equilibria of the unperturbed game when the sequence of perturbed games converges to the unperturbed one in an appropriate sense. The question whether such limit property extends to the...

In this paper we consider a model of games of incomplete information under ambiguity in which players are endowed with variational preferences. We provide an existence result for the corresponding mixed equilibrium notion. Then we study the limit behavior of equilibria under perturbations on the...