natolambert: importance-sampling fixes for train-inference mismatch dominate RL research

natolambert · x · 2026-10-31

AI researcher Nathan Lambert notes that while reading the Score Centering RL paper, he found a great appendix table comparing importance-sampling-based methods for train-inference mismatch in RL — which he considers the biggest focus of RL algorithm research since the GRPO takeoff.

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