A solidarity value for n-person transferable utility games

In this paper, the authors introduce axiomatically a new value for cooperative TU games satisfying the efficiency, additivity, and symmetry axioms of Shapley and some new postulate connected with the average marginal contributions of the members of coalitions which can form. The present solution is referred to as the solidarity value. The reason is that its interpretation can be based on the assumption that if a coalition, say S, forms, then the players who contribute to S more than the average marginal contribution of a member of S support in some sense their ‘weaker’ partners in S. Sometimes, it happens that the solidarity value belongs to the core of a game while the Shapley value does not.