Contrastive Learning to Improve Retrieval for Real-World Fact Checking

Aniruddh Sriram, Fangyuan Xu, Eunsol Choi, Greg Durrett


Abstract
Recent work on fact-checking addresses a realistic setting where models incorporate evidence retrieved from the web to decide the veracity of claims. A bottleneck in this pipeline is in retrieving relevant evidence: traditional methods may surface documents directly related to a claim, but fact-checking complex claims requires more inferences. For instance, a document about how a vaccine was developed is relevant to addressing claims about what it might contain, even if it does not address them directly. We present Contrastive Fact-Checking Reranker (CFR), an improved retriever for this setting. By leveraging the AVeriTeC dataset, which annotates subquestions for claims with human written answers from evidence documents, we fine-tune Contriever with a contrastive objective based on multiple training signals, including distillation from GPT-4, evaluating subquestion answers, and gold labels in the dataset. We evaluate our model on both retrieval and end-to-end veracity judgments about claims. On the AVeriTeC dataset, we find a 6% improvement in veracity classification accuracy. We also show our gains can be transferred to FEVER, ClaimDecomp, HotpotQA, and a synthetic dataset requiring retrievers to make inferences.
Anthology ID:
2024.fever-1.28
Volume:
Proceedings of the Seventh Fact Extraction and VERification Workshop (FEVER)
Month:
November
Year:
2024
Address:
Miami, Florida, USA
Editors:
Michael Schlichtkrull, Yulong Chen, Chenxi Whitehouse, Zhenyun Deng, Mubashara Akhtar, Rami Aly, Zhijiang Guo, Christos Christodoulopoulos, Oana Cocarascu, Arpit Mittal, James Thorne, Andreas Vlachos
Venue:
FEVER
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
264–279
Language:
URL:
https://aclanthology.org/2024.fever-1.28
DOI:
Bibkey:
Cite (ACL):
Aniruddh Sriram, Fangyuan Xu, Eunsol Choi, and Greg Durrett. 2024. Contrastive Learning to Improve Retrieval for Real-World Fact Checking. In Proceedings of the Seventh Fact Extraction and VERification Workshop (FEVER), pages 264–279, Miami, Florida, USA. Association for Computational Linguistics.
Cite (Informal):
Contrastive Learning to Improve Retrieval for Real-World Fact Checking (Sriram et al., FEVER 2024)
Copy Citation:
PDF:
https://aclanthology.org/2024.fever-1.28.pdf