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arXiv · 2101.11861

Symmetric equilibrium of multi-agent reinforcement learning in repeated prisoner's dilemma

Yuki Usui·Masahiko Ueda
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Abstract

We investigate the repeated prisoner's dilemma game where both players alternately use reinforcement learning to obtain their optimal memory-one strategies. We theoretically solve the simultaneous Bellman optimality equations of reinforcement learning. We find that the Win-stay Lose-shift strategy, the Grim strategy, and the strategy which always defects can form symmetric equilibrium of the mutual reinforcement learning process amongst all deterministic memory-one strategies.

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Yuki Usui, Masahiko Ueda. 2021-01-28. Symmetric equilibrium of multi-agent reinforcement learning in repeated prisoner's dilemma. https://doi.org/10.1016/j.amc.2021.126370

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