Learning Kernel-Based MDPs from Episodic Preferential Feedback
- URL: http://arxiv.org/abs/2605.23650v2
- Date: Mon, 25 May 2026 02:19:44 GMT
- Title: Learning Kernel-Based MDPs from Episodic Preferential Feedback
- Abstract summary: We present a theoretical study of preference-only learning in episodic kernel MDPs.<n>We develop preference-based value estimation and confidence sets tailored to end-of-episode comparisons.<n>We prove high-probability regret bounds that scale sublinearly in the number of episodes, implying that the value of the learned policy converges to that of the optimal policy.
- Score: 14.488515539527995
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Human feedback often arrives as preferences rather than calibrated numeric rewards, motivating reinforcement learning from preferential feedback, also referred to as reinforcement learning from human feedback (RLHF). We present a rigorous theoretical study of preference-only learning in episodic kernel MDPs. In each episode, the learner deploys two policies from a common start state and receives a single binary label indicating which trajectory is preferred, modeled by a Bradley--Terry--Luce link on the difference of cumulative (unobserved) rewards. Under kernel-based assumptions on the reward and transition functions (one of the most general models amenable to theoretical analysis) we develop preference-based value estimation and confidence sets tailored to end-of-episode comparisons. We prove high-probability regret bounds that scale sublinearly in the number of episodes, implying that the value of the learned policy converges to that of the optimal policy.
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