FactCorrector: A Graph-Inspired Approach to Long-Form Factuality Correction of Large Language Models

Javier Carnerero-Cano, Massimiliano Pronesti, Radu Marinescu, Tigran T. Tchrakian, James Barry, Jasmina Gajcin, Yufang Hou, Alessandra Pascale, Elizabeth M. Daly


Abstract
Large language models (LLMs) are widely used in knowledge-intensive applications but often generate factually incorrect responses. A promising approach to rectify these flaws is correcting LLMs using feedback. Therefore, in this paper, we introduce FactCorrector, a new post-hoc correction method that adapts across domains without retraining and leverages structured feedback about the factuality of the original response to generate a correction. To support rigorous evaluations of factuality correction methods, we also develop the VELI5 benchmark, a novel dataset containing systematically injected factual errors and ground-truth corrections. Experiments on VELI5 and several popular long-form factuality datasets show that the FactCorrector approach significantly improves factual precision while preserving relevance, outperforming strong baselines. We release our code at https://ibm.biz/factcorrector.
Anthology ID:
2026.acl-long.2147
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
Venue:
ACL
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Publisher:
Association for Computational Linguistics
Note:
Pages:
46278–46307
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URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.2147/
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Cite (ACL):
Javier Carnerero-Cano, Massimiliano Pronesti, Radu Marinescu, Tigran T. Tchrakian, James Barry, Jasmina Gajcin, Yufang Hou, Alessandra Pascale, and Elizabeth M. Daly. 2026. FactCorrector: A Graph-Inspired Approach to Long-Form Factuality Correction of Large Language Models. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 46278–46307, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
FactCorrector: A Graph-Inspired Approach to Long-Form Factuality Correction of Large Language Models (Carnerero-Cano et al., ACL 2026)
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https://preview.aclanthology.org/ingest-acl/2026.acl-long.2147.pdf
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