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arXiv · 2310.08089

Learning Regularized Monotone Graphon Mean-Field Games

Abstract

This paper studies two fundamental problems in regularized Graphon Mean-Field Games (GMFGs). First, we establish the existence of a Nash Equilibrium (NE) of any $λ$-regularized GMFG (for $λ\geq 0$). This result relies on weaker conditions than those in previous works for analyzing both unregularized GMFGs ($λ=0$) and $λ$-regularized MFGs, which are special cases of GMFGs. Second, we propose provably efficient algorithms to learn the NE in weakly monotone GMFGs, motivated by Lasry and Lions [2007]. Previous literature either only analyzed continuous-time algorithms or required extra conditions to analyze discrete-time algorithms. In contrast, we design a discrete-time algorithm and derive its convergence rate solely under weakly monotone conditions. Furthermore, we develop and analyze the action-value function estimation procedure during the online learning process, which is absent from algorithms for monotone GMFGs. This serves as a sub-module in our optimization algorithm. The efficiency of the designed algorithm is corroborated by empirical evaluations.

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BibTeXRIS

Fengzhuo Zhang, Vincent Y. F. Tan, Zhaoran Wang, Zhuoran Yang. 2023-10-12. Learning Regularized Monotone Graphon Mean-Field Games. https://arxiv.org/abs/2310.08089

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