Abstract:

We exhibit a general class of interactive decision situations in which all the agents benefit from more information. This class includes as a special case the classical comparison of statistical experiments   la Blackwell.More specifically, we consider pairs consisting of a game with incomplete information G and an information structure S such that the extended game “(G,S) has a unique Pareto payoff profile u. We prove that u is a Nash payoff profile of “(G,S), and that for any information structure that is coarser than S, all Nash payoff profiles of “(G,T) are dominated by u. We then prove that our condition is also necessary in the following sense: Given any convex compact polyhedron of payoff profiles, whose Pareto frontier is not a singleton, there exists an extended game “(G,S) with that polyhedron as the convex hull of feasible payoffs, an information structure T coarser than S and a player i who strictly prefers a Nash equilibrium in “(G,T) to any Nash equilibrium in “(G,S).

Website