Quantifying the Self-Interest Level of Markov Social Dilemmas
Richard Willis, Yali Du, Joel Z Leibo, Michael Luck
TL;DR
The paper tackles measuring and inducing cooperation in complex Markov social dilemmas by defining and estimating the self-interest level $s^*$. It extends reward-transfer ideas from normal-form games to Markov games and uses multi-agent reinforcement learning with curriculum training to empirically identify the threshold at which reward exchange promotes cooperative equilibria. Applied to three Melting Pot environments, the method yields $s^*$ values around $0.29$ for Commons Harvest and $0.25$–$0.29$ for Clean Up, while Externality Mushrooms does not exhibit a Markov social dilemma structure, limiting the effectiveness of reward exchange. The work offers a practical metric and mechanism design insight for fostering cooperation in multi-agent systems and suggests avenues for broader applicability and refinement in heterogeneous or larger-scale settings.
Abstract
This paper introduces a novel method for estimating the self-interest level of Markov social dilemmas. We extend the concept of self-interest level from normal-form games to Markov games, providing a quantitative measure of the minimum reward exchange required to align individual and collective interests. We demonstrate our method on three environments from the Melting Pot suite, representing either common-pool resources or public goods. Our results illustrate how reward exchange can enable agents to transition from selfish to collective equilibria in a Markov social dilemma. This work contributes to multi-agent reinforcement learning by providing a practical tool for analysing complex, multistep social dilemmas. Our findings offer insights into how reward structures can promote or hinder cooperation, with potential applications in areas such as mechanism design.
