Policy Space Response Oracles: A Survey
This is an incremental survey paper summarizing existing research on PSRO for researchers in game theory and multi-agent systems.
This survey examines the Policy Space Response Oracles (PSRO) framework, which addresses scalability limitations in game theory by focusing on subsets of strategies to represent large games efficiently, surveying its applications and open research questions.
Game theory provides a mathematical way to study the interaction between multiple decision makers. However, classical game-theoretic analysis is limited in scalability due to the large number of strategies, precluding direct application to more complex scenarios. This survey provides a comprehensive overview of a framework for large games, known as Policy Space Response Oracles (PSRO), which holds promise to improve scalability by focusing attention on sufficient subsets of strategies. We first motivate PSRO and provide historical context. We then focus on the strategy exploration problem for PSRO: the challenge of assembling effective subsets of strategies that still represent the original game well with minimum computational cost. We survey current research directions for enhancing the efficiency of PSRO, and explore the applications of PSRO across various domains. We conclude by discussing open questions and future research.