This paper is devoted to the study of opportunity sets comparisons when the sets may contain options whose characteristics are not completely known. We propose a suitable environment in which this problem can be approached, and provide axiomatic characterizations of several rules for ranking...

In this paper we characterize axiomatically a ranking method that compares positions in hierarchies in terms of the influence that they provide on the evolvement of knowledge. The comparison takes into account the number of direct and indirect subordinates of the positions and is based on the...

Numerous works in the last decade have analyzed the question of how to compare opportunity sets as a way to measure and evaluate individual freedom of choice. This paper defends that, in many contexts, external procedural aspects that are associated to an opportunity set should be taken into...

A coalitional matching is a two-sided matching problem in which agents on each side of the market may form coalitions such as student groups and research teams who - when matched - form universities. We assume that each researcher has preferences over the research teams he would like to work in...

We consider hedonic coalition formation games that are induced by a simple TU-game and a cooperative solution. For such models, Shenoy's (1979) absence of the paradox of smaller coalitions provides a sufficient condition for core existence. We present three different versions of his condition in...

We investigate a situation in which gains from cooperation are represented by a cooperative TU-game and a solution proposes a division of coalitional worths. In addition, asymmetries among players outside the game are captured by a vector of exogenous weights. If a solution measures players'...

In this paper we provide characterizations of convex games and total clan games by using properties of their corresponding marginal games. We show that a "dualize and restrict" procedure transforms total clan games with zero worth for the clan into monotonic convex games. Furthermore, each...

In this paper we axiomatically characterize two recursive procedures for defining a social group. The first procedure starts with the set of all individuals who are defined by everyone in the society as group members, while the starting point of the second procedure is the set of all individuals...

In this paper we study hedonic coalition formation games in which players' preferences over coalitions are induced by a semi-value of a monotonic simple game with veto control. We consider partitions of the player set in which the winning coalition contains the union of all minimal winning...

We consider the class of proper monotonic simple games and study coalition formation when an exogenous weight vector and a solution concept are combined to guide the distribution power within winning coalitions. These distributions induce players' preferences over coalitions in a hedonic game....