Explaining Sources of Uncertainty in Automated Fact-Checking

Jingyi Sun, Greta Warren, Irina Shklovski, Isabelle Augenstein


Abstract
Human–AI collaboration in knowledge-intensive tasks such as fact-checking requires understanding model uncertainty in multi-document reasoning amid conflicting/agreeing evidence. Yet, existing methods only express uncertainty as numbers or hedges without revealing which evidence conflicts cause the uncertainty, leaving users unable to resolve disagreements. We present CLUE (**C**onflict- Agreement-aware **L**anguage-model **U**ncertainty **E**xplanations), a plug-and-play white-box framework that, to our knowledge, is the first to generate natural-language explanations of model uncertainty grounded in conflicting/agreeing evidence. CLUE (i) identifies span-level claim–evidence and inter-evidence relations that signal conflict or agreement without supervision, and (ii) uses these relations to steer explanation generation, articulating how they drive the model’s uncertainty. Across three language models and two fact-checking datasets, CLUE produces explanations that more faithfully track model uncertainty and better align with the model’s fact-checking decisions than span-agnostic explanation prompting; human raters also judge them more helpful, more informative, less redundant, and more logically consistent with the input. By explicitly tying uncertainty to evidence conflicts and agreements, CLUE supports practical fact-checking and other tasks that require reasoning over complex, conflicting information.
Anthology ID:
2026.acl-long.2110
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
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
45510–45534
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.2110/
DOI:
Bibkey:
Cite (ACL):
Jingyi Sun, Greta Warren, Irina Shklovski, and Isabelle Augenstein. 2026. Explaining Sources of Uncertainty in Automated Fact-Checking. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 45510–45534, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Explaining Sources of Uncertainty in Automated Fact-Checking (Sun et al., ACL 2026)
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PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.2110.pdf
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