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arXiv · 1609.04099

A Semi-Potential for Finite and Infinite Sequential Games (Extended Abstract)

Stéphane Le Roux·Arno Pauly
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Abstract

We consider a dynamical approach to sequential games. By restricting the convertibility relation over strategy profiles, we obtain a semi-potential (in the sense of Kukushkin), and we show that in finite games the corresponding restriction of better-response dynamics will converge to a Nash equilibrium in quadratic time. Convergence happens on a per-player basis, and even in the presence of players with cyclic preferences, the players with acyclic preferences will stabilize. Thus, we obtain a candidate notion for rationality in the presence of irrational agents. Moreover, the restriction of convertibility can be justified by a conservative updating of beliefs about the other players strategies. For infinite sequential games we can retain convergence to a Nash equilibrium (in some sense), if the preferences are given by continuous payoff functions; or obtain a transfinite convergence if the outcome sets of the game are Delta^0_2 sets.

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Stéphane Le Roux, Arno Pauly. 2016-09-14. A Semi-Potential for Finite and Infinite Sequential Games (Extended Abstract). https://doi.org/10.4204/eptcs.226.17

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