arXiv AI By Arnav Raj

PEBS: Per-rater Empirical-Bayes Shrinkage for RLHF Reward-Model Calibration

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arXiv:2606. 27578v1 Announce Type: cross Abstract: Reward models for Reinforcement Learning from Human Feedback (RLHF) pool preferences across thousands of annotators and fit one global affine calibrator, collapsing raters with systematically different rating-scale offsets and slopes into a single average-rater fit that does not match any individual annotator.

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