LoRE: Enhancing Search Relevance with Progressive Chain-of-Thought and Preference Alignment

Chenji Lu, Zhuo Chen, Hui Zhao, Zhiyuan Zeng, Gang Zhao, Junjie Ren, Lihaoran, Songyan Liu, Pengjie Wang, Chuan Yu, Jian Xu, Bo Zheng


Abstract
E-commerce search relevance is a critical component of retrieval systems. While Large Language Models (LLMs)-driven Chain-of-Thought (CoT) modeling has become the dominant paradigm and yielded significant gains, a critical gap remains: the absence of a systematic definition for comprehensive relevance reasoning, which leads to significant blind spots in current approaches. In this paper, we deconstruct the task into three core competencies: reasoning knowledge, multi-modal understanding, and rule awareness. Accordingly, we propose LoRE(Large Generative Model for Search Relevance), a novel two-stage training framework. We first employ an SFT phase to instill these capabilities via a progressive CoT synthesis pipeline, followed by a Reinforcement Learning(RL) phase, which serves as a regularizer, pruning redundant logic to achieve precise and robust adjudication. Extensive experiments validate LoRE, outperforming GPT-5 by 29.1% in Macro-F1 and achieving a 27% online gain, offering a vital reference for industrial domain-specific post-training.
Anthology ID:
2026.findings-acl.1536
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
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San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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Findings
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Publisher:
Association for Computational Linguistics
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Pages:
30754–30768
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1536/
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Cite (ACL):
Chenji Lu, Zhuo Chen, Hui Zhao, Zhiyuan Zeng, Gang Zhao, Junjie Ren, Lihaoran, Songyan Liu, Pengjie Wang, Chuan Yu, Jian Xu, and Bo Zheng. 2026. LoRE: Enhancing Search Relevance with Progressive Chain-of-Thought and Preference Alignment. In Findings of the Association for Computational Linguistics: ACL 2026, pages 30754–30768, San Diego, California, United States. Association for Computational Linguistics.
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LoRE: Enhancing Search Relevance with Progressive Chain-of-Thought and Preference Alignment (Lu et al., Findings 2026)
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