A regularization method for bilevel problems with lower level defined by Nash equilibria is considered and a concept of \viscosity solution" associated to such a regularization is introduced. Sufficient conditions for the existence of viscosity solutions are given and applications to optimistic...

The great interest into hierarchical optimization problems and the increasing use of game theory in many economic or engineering applications led to investigate optimization problems with constraints described by the solutions to a quasi-variational inequality (variational problems having...

In this paper, we look at the classical problem of aggregating individual utilities and study social orderings which are based on the concept of Ordered Weighted Averaging (OWA) Aggregating Operator. In these social orderings, called OWA social welfare functions (swf), weights are assigned a...

MinSup problems with constraints described by quasi-equilibrium problems are considered in Banach spaces. The solutions set of such problems may be empty even in very good situations, so the aim of this paper is twofold. First, we determine appropriate regularizations which allow to...

We consider a two-stage model where a leader, according to its risk-averse proneness, solves a MinSup problem with constraints corresponding to the reaction sets of a follower and defined by the solutions of a quasi-variational inequality (i.e. a variational inequality having constraint sets...

Multicriteria games describe strategic interactions in which players, having more than one criterion to take into account, don't have an a-priori opinion on the rel- ative importance of all these criteria. Roemer (2005) introduces an organizational interpretation of the concept of equilibrium:...

Given their importance in determining the outcome of many economic interactions, different models have been proposed to determine how social networks form and which structures are stable. In Bala and Goyal (2000), the one-sided link formation model has been considered, which is based on a...

The famous Harsanyi's (1973) Theorem states that generically a finite game has an odd number of Nash equilibria in mixed strategies. In this paper, we show that for finite multicriteria games (games with vector-valued payoffs) this kind of result does not hold. In particular, we show, by...

We present optimality conditions for bilevel optimal control problems where the upper level, to be solved by a leader, is a scalar optimal control problem and the lower level, to be solved by several followers, is a multiobjective convex optimal control problem. Multiobjective optimal control...

We model climate negotiations as a two-stage game. In the first stage of the game, players have to agree on a global emission cap (GEC). In the second stage, they non-cooperatively choose either their emission level or their emission quota, depending on whether emission trading is allowed, under...