Meta-Rewarding Language Models: Self-Improving Alignment with LLM-as-a-Meta-Judge

Tianhao Wu, Weizhe Yuan, Olga Golovneva, Jing Xu, Yuandong Tian, Jiantao Jiao, Jason E Weston, Sainbayar Sukhbaatar


Abstract
Large Language Models (LLMs) are rapidly surpassing human knowledge in many domains. While improving these models traditionally relies on costly human data, recent self-rewarding mechanisms have shown that LLMs can improve by judging their own responses instead of relying on human labelers. However, existing methods have primarily focused on improving model responses rather than judgment capabilities, resulting in rapid saturation during iterative training. To address this issue, we introduce a novel Meta-Rewarding step to the self-improvement process, where the model judges its own judgements and uses that feedback to refine its judgment skills. Surprisingly, this unsupervised approach improves the model’s ability to judge and follow instructions, as demonstrated by a win rate improvement of Llama-3-8B-Instruct from 22.9% to 39.4% on AlpacaEval 2, and 20.6% to 29.1% on Arena-Hard. These results strongly suggest the potential for self-improving models without human supervision.
Anthology ID:
2025.emnlp-main.583
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
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EMNLP
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Publisher:
Association for Computational Linguistics
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Pages:
11548–11565
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https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.583/
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Cite (ACL):
Tianhao Wu, Weizhe Yuan, Olga Golovneva, Jing Xu, Yuandong Tian, Jiantao Jiao, Jason E Weston, and Sainbayar Sukhbaatar. 2025. Meta-Rewarding Language Models: Self-Improving Alignment with LLM-as-a-Meta-Judge. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 11548–11565, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
Meta-Rewarding Language Models: Self-Improving Alignment with LLM-as-a-Meta-Judge (Wu et al., EMNLP 2025)
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