FACTA: Structured Fact Alignment for Multi-Hop Retrieval-Augmented Generation

Jiahao Li, Yongxiu Xu, Xumeng Zhang, Hongbo Xu, Minghao Tang, Yubin Wang, Gaopeng Gou


Abstract
Although Retrieval-Augmented Generation (RAG) empowers Large Language Models (LLMs) with external knowledge, current frameworks struggle with complex multi-hop reasoning as they fundamentally rely on shallow retrieval signals. Existing methods typically employ coarse semantic matching or entity-centric graph expansion, which often retrieve textually similar but factually irrelevant evidence, injecting noise into the reasoning process. To overcome this limitation, we introduce FACTA, a structured fact alignment framework for multi-hop retrieval. FACTA bridges the gap between a query’s step-wise information demand and a document’s information supply by translating both into structured, explicit factual triples. Through a dual mechanism of triple-level fact matching and multi-signal document reranking, FACTA better identifies evidence that satisfies the factual prerequisites of each reasoning hop. Extensive evaluations on three multi-hop QA benchmarks show that FACTA substantially outperforms state-of-the-art baselines, demonstrating that structured fact-centric retrieval effectively reduces reasoning noise and enhances the accuracy of multi-hop generation.
Anthology ID:
2026.findings-aacl.90
Volume:
Findings of the Association for Computational Linguistics: IJCNLP-AACL 2026
Month:
November
Year:
2026
Address:
Hengqin, China
Editors:
Yue Zhang, Ruifeng Xu, Ayu Purwarianti, Tong Rong, Jun Suzuki
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1815–1831
Language:
URL:
https://aclanthology.org/2026.findings-aacl.90/
DOI:
Bibkey:
Cite (ACL):
Jiahao Li, Yongxiu Xu, Xumeng Zhang, Hongbo Xu, Minghao Tang, Yubin Wang, and Gaopeng Gou. 2026. FACTA: Structured Fact Alignment for Multi-Hop Retrieval-Augmented Generation. In Findings of the Association for Computational Linguistics: IJCNLP-AACL 2026, pages 1815–1831, Hengqin, China. Association for Computational Linguistics.
Cite (Informal):
FACTA: Structured Fact Alignment for Multi-Hop Retrieval-Augmented Generation (Li et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-aacl.90.pdf