copy-less-ground-more-overcoming-repetitive-copying-in-long-context-reasoning-via-evidence-aware-reinforcement-learning-79f22dc3·1 events·first seen Aliases: Copy Less, Ground More: Overcoming Repetitive Copying in Long-Context Reasoning via Evidence-Aware Reinforcement Learning
Researchers identify 'repetitive copying' as a pervasive failure mode in long-context LLMs, where models copy input text into reasoning traces instead of solving problems, worsening with context length. They propose GEAR (Grounding Evidence-Aware Reward), a reinforcement learning reward shaping method that adds a grounding reward for overlap with key evidence and a penalty for overlap with irrelevant distractor context. GEAR shows consistent improvements of up to +4.6 average points over standard accuracy-based RL across multiple model scales and benchmarks, with larger gains at longer contexts and reduced reasoning trace length. The work also introduces an automated pipeline for constructing evidence-annotated training data from arbitrary documents.