ConsistRM: Improving Generative Reward Models via Consistency-Aware Self-Training

Yu Liang, Liangxin Liu, Longzheng Wang, Wangyan, Zhang Yueyang, Long Xia, Zhiyuan Sun, Daiting Shi


Abstract
Generative reward models (GRMs) have emerged as a promising approach for aligning Large Language Models (LLMs) with human preferences by offering greater representational capacity and flexibility than traditional scalar reward models. However, GRMs face two major challenges: reliance on costly human-annotated data restricts scalability, and self-training approaches often suffer from instability and vulnerability to reward hacking. To address these issues, we propose ConsistRM, a self-training framework that enables effective and stable GRM training without human annotations. ConsistRM incorporates the Consistency-Aware Answer Reward, which produces reliable pseudo-labels with temporal consistency, thereby providing more stable model optimization. Moreover, the Consistency-Aware Critique Reward is introduced to assess semantic consistency across multiple critiques and allocates fine-grained and differentiated rewards. Experiments on five benchmark datasets across four base models demonstrate that ConsistRM outperforms vanilla Reinforcement Fine-Tuning (RFT) by an average of 1.5%. Further analysis shows that ConsistRM enhances output consistency and mitigates position bias caused by input order, highlighting the effectiveness of consistency-aware rewards in improving GRMs.Our implementation is available at https://github.com/yuliangCarmelo/ConsistRM.
Anthology ID:
2026.acl-long.1830
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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ACL
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Publisher:
Association for Computational Linguistics
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Pages:
39449–39466
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https://preview.aclanthology.org/ingest-acl/2026.acl-long.1830/
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Cite (ACL):
Yu Liang, Liangxin Liu, Longzheng Wang, Wangyan, Zhang Yueyang, Long Xia, Zhiyuan Sun, and Daiting Shi. 2026. ConsistRM: Improving Generative Reward Models via Consistency-Aware Self-Training. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 39449–39466, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
ConsistRM: Improving Generative Reward Models via Consistency-Aware Self-Training (Liang et al., ACL 2026)
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https://preview.aclanthology.org/ingest-acl/2026.acl-long.1830.pdf
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