On the strong hybrid solution of an n-person game

We propose a new notion of coalitional equilibrium, the strong hybrid solution, which is a refinement of Zhao’s hybrid solution. It is well suited to study situations where people cooperate within coalitions but where coalitions compete with one another. In the strong hybrid solution, as opposed to the hybrid solution, the strategy profile assigned to each coalition is strongly Pareto optimal. We show that there exists a strong hybrid solution whenever preferences are partially quasi-transferable.