HyperProve: Answer-Guided Hypergraph Expansion for Multi-Hop Question Answering

Nguyen Phu An, Dung Nguyen Quang, Luu Hieu An, Linh Ngo Van, Trung Le, Thien Huu Nguyen


Abstract
Multi-hop question answering often fails when retrieval treats evidence as isolated matches to the original question, since the facts needed to answer a complex question are usually connected through intermediate entities, relations, and constraints. We propose HyperProve, a retrieval-augmented QA framework that addresses this challenge by coupling question decomposition with answer-conditioned expansion over a hypergraph of atomic facts. HyperProve does not use atomic facts, hypergraphs, or iterative retrieval in isolation; instead, it carries intermediate answers and supporting hyperedges as retrieval state, then uses that state to bias the next local hypergraph expansion. This design enables HyperProve to construct coherent evidence chains for final answer generation while making the retrieval process stateful and fact-centered. Across multi-hop QA benchmarks, HyperProve achieves the best overall performance in our evaluation, outperforming the strongest baselines by an average relative improvement of 6.2% in answer accuracy and 4.9% in F1.
Anthology ID:
2026.emnlp-main.212
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
4867–4882
Language:
URL:
https://aclanthology.org/2026.emnlp-main.212/
DOI:
Bibkey:
Cite (ACL):
Nguyen Phu An, Dung Nguyen Quang, Luu Hieu An, Linh Ngo Van, Trung Le, and Thien Huu Nguyen. 2026. HyperProve: Answer-Guided Hypergraph Expansion for Multi-Hop Question Answering. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 4867–4882, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
HyperProve: Answer-Guided Hypergraph Expansion for Multi-Hop Question Answering (An et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.212.pdf