🤖 AI Summary
This study addresses the challenge of modeling evolutionary game dynamics in finite, small populations. We propose a unified analytical framework based on Markov chains, explicitly constructing transition probability matrices to model canonical games—including iterated prisoner’s dilemma, stag hunt, and rock–paper–scissors—under three update rules: best response, pairwise comparison, and proportional imitation. Our key contributions are threefold: (i) the first analytically tractable matrix-based modeling of multiple games and update mechanisms within small-population settings; (ii) exact characterization of absorbing state structures, stationary distributions, and convergence rates; and (iii) identification of equilibrium selection’s sensitivity to and structural dependence on the choice of update rule in finite populations. The framework yields a computationally feasible, quantitatively comparable theoretical tool for predicting evolutionary outcomes in small-scale interactive systems.
📝 Abstract
We construct and study the transition probability matrix of evolutionary games in which the number of players is finite (and relatively small) of such games. We use a simplified version of the population games studied by Sandholm. After laying out a general framework we concentrate on specific examples, involving the Iterated Prisoner's Dilemma, the Iterated Stag Hunt, and the Rock-Paper-Scissors game. Also we consider several revision protocols: Best Response, Pairwise Comparison, Pairwise Proportional Comparison etc. For each of these we explicitly construct the MC transition probability matrix and study its properties.