Best of Both Worlds: Regret Minimization versus Minimax Play
- URL: http://arxiv.org/abs/2502.11673v1
- Date: Mon, 17 Feb 2025 11:04:01 GMT
- Title: Best of Both Worlds: Regret Minimization versus Minimax Play
- Authors: Adrian Müller, Jon Schneider, Stratis Skoulakis, Luca Viano, Volkan Cevher,
- Abstract summary: We show that our results allow us to guarantee to risk at most $O(1)$ loss while being able to gain $Omega(T)$ from exploitable opponents.
- Score: 57.68976579579758
- License:
- Abstract: In this paper, we investigate the existence of online learning algorithms with bandit feedback that simultaneously guarantee $O(1)$ regret compared to a given comparator strategy, and $O(\sqrt{T})$ regret compared to the best strategy in hindsight, where $T$ is the number of rounds. We provide the first affirmative answer to this question. In the context of symmetric zero-sum games, both in normal- and extensive form, we show that our results allow us to guarantee to risk at most $O(1)$ loss while being able to gain $\Omega(T)$ from exploitable opponents, thereby combining the benefits of both no-regret algorithms and minimax play.
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