Robust Multi-Agent Decision-Making in Finite-Population Games
Shinkyu Park, Lucas C. D. Bezerra
TL;DR
This work advances robust decision-making in finite-population games by analyzing the Kullback-Leibler Divergence Regularized Learning (KLD-RL) protocol, which couples stochastic population dynamics with a softmax-like update controlled by $\eta$ and a reference distribution $\theta$. By leveraging $\delta$-passivity and $\delta$-antipassivity, the authors derive stability results for the closed-loop EDM under delayed, noisy payoff observations and quantify how the revision rate $\lambda$ and regularization $\eta$ trade off convergence speed, noise sensitivity, and long-run variance. A central bound shows the deviation between the interpolated population state $\widehat{X}^N$ and the regularized best-response $C^{\eta,\theta}(p)$ scales with $(\lambda^2\eta)^{-1}$, while a Lipschitz property of $C^{\eta,\theta}$ in $p$ allows mitigating reduced $\lambda$ via larger $\eta$. Simulations on a finite population with task-allocation dynamics confirm that properly tuned $\lambda$ and $\eta$ improve noise robustness and convergence to the equilibrium $x^*$, and the work highlights the potential to learn $x^*$ and $\theta$ in future data-driven extensions.
Abstract
We study the robustness of an agent decision-making model in finite-population games, with a particular focus on the Kullback-Leibler Divergence Regularized Learning (KLD-RL) model. Specifically, we examine how the model's parameters influence the impact of various sources of noise and modeling inaccuracies -- factors commonly encountered in engineering applications of population games -- on agents' decision-making. Our analysis provides insights into how these parameters can be effectively tuned to mitigate such effects. Theoretical results are supported by numerical examples and simulation studies that validate the analysis and illustrate practical strategies for parameter selection.
