Solving Decision-Dependent Games by Learning from Feedback
Killian Wood, Ahmed Zamzam, Emiliano Dall'Anese
TL;DR
The paper addresses solving stochastic Nash equilibria when data distributions are decision-dependent and unknown. It introduces a learning-based plug-in framework that first estimates a distributional map $D_i$ from responses and then optimizes using the learned map in a distributed gradient setting, yielding a Nash equilibrium of the approximate game. Theoretical guarantees include high-probability ERM bounds, uniform gradient bounds for map estimation, and linear convergence of the distributed gradient method to a neighborhood of the equilibrium, with decaying step-sizes enabling convergence to the true point. Numerical experiments on an electric vehicle charging market with real data demonstrate the practical viability and impact of the approach for decision-dependent data in multi-agent settings.
Abstract
This paper tackles the problem of solving stochastic optimization problems with a decision-dependent distribution in the setting of stochastic strongly-monotone games and when the distributional dependence is unknown. A two-stage approach is proposed, which initially involves estimating the distributional dependence on decision variables, and subsequently optimizing over the estimated distributional map. The paper presents guarantees for the approximation of the cost of each agent. Furthermore, a stochastic gradient-based algorithm is developed and analyzed for finding the Nash equilibrium in a distributed fashion. Numerical simulations are provided for a novel electric vehicle charging market formulation using real-world data.
