AI Frontier Lectures

Dec 9, 2025 · Artificial Intelligence

Can Token‑Level Surrogates Stabilize RL for Large Language Models? A Deep Dive

This article analyzes why optimizing sequence‑level rewards for LLMs with token‑level surrogate objectives can improve reinforcement‑learning stability, explains the theoretical conditions required, introduces Routing Replay for MoE models, and presents extensive experiments validating the approach.