Working Papers, Department of Economics, Rutgers, the State University of New Jersey 2008,07
We show that local potential maximizer () with constant weights is stochastically stable in the log-linear dynamics provided that the payoff function or the associated local potential function is supermodular. We illustrate and discuss, through a series of examples, the use of our main results as well as other concepts closely related to local potential maximizer: weighted potential maximizer, p-dominance. We also discuss the log-linear processes where each player's stochastic choice rule converges to the best response rule at different rates. For 2 x 2 games, we examine a modified log-linear dynamics (relative log-linear dynamics) under which local potential maximizer with strictly positive weights is stochastically stable. This in particular implies that for 2 x 2 games a strict (p1,p2)-dominant equilibrium with p1+p2<1 is stochastically stable under the new dynamics.
log-linear dynamics stochastic stability local potential maximizer equilibrium selection comparison of Markov chains