Breaking the Symmetry: Optimal Conventions in Repeated Symmetric Games

We analyze the problem of coordinating upon asymmetric equilibria in a symmetric game, such as the battle-of-the-sexes. In repeated interaction, asymmetric coordination is possible possible via symmetric repeated game strategies. This requires that players randomize initially and adopt a convention, i.e a (symmetric) rule which maps asymmetric realizations to asymmetric continuation paths. The multiplicity of possible conventions gives rise to a coordination problem at a higher level if the game is one of pure coordination. However, if there is a slight conflict of interest between players, a unique optimal convention often exists. The optimal convention is egalitarian, and thereby increases the probability of coordination.