Distribution Equilibrium I: definition and Examples.

In a 2-person Nash equilibrium any pure strategy is evaluated against the same mixed strategy of the opponent. The equilibrium condition says that all pure strategies used at equilibrium are best replies, hence they give the same payoff. We keep here the last two requirements (best reply and same payoff) but realx the first one (facing the same opponent's strategy) in the spirit of correlated distributions. We obtain a concept that has a natural interpretation in terms of equilibrium of populations: the various active genotypes have specific fitness and present also different norms of behavior.