Voici les éléments 1 - 2 sur 2
  • Publication
    Accès libre
    Deterministic approximation of stochastic evolution in games
    (2003) ;
    Weibull, Jorgen W
    This paper provides deterministic approximation results for stochastic processes that arise when finite populations recurrently play finite games. The processes are Markov chains, and the approximation is defined in continuous time as a system of ordinary differential equations of the type studied in evolutionary game theory. We establish precise connections between the long-run behavior of the discrete stochastic process, for large populations, and its deterministic flow approximation. In particular, we provide probabilistic bounds on exit times from and visitation rates to neighborhoods of attractors; to the deterministic flow. We sharpen these results in the special case of ergodic processes.
  • Publication
    Accès libre
    Stochastic approximation algorithms with constant step size whose average is cooperative
    (1999) ;
    Hirsch, Morris W
    We consider stochastic approximation algorithms with constant step size whose average ordinary differential equation (ODE) is cooperative and irreducible. We show that, under mild conditions on the noise process, invariant measures and empirical occupations measures of the process weakly converge (as the time goes to infinity and the step size goes to zero) toward measures which are supported by stable equilibria of the ODE. These results are applied to analyzing the long-term behavior of a class of learning processes arising in game theory.