Portuguese Automated Fact-checking: Information Retrieval with Claim extraction

Juliana Gomes, Eduardo Garcia, Arlindo Rodrigues Galvão Filho


Abstract
Current Portuguese Automated Fact-Checking (AFC) research often relies on datasets lacking integrated external evidence crucial for comprehensive verification. This study addresses this gap by systematically enriching Portuguese misinformation datasets. We retrieve web evidence by simulating user information-seeking behavior, guided by core claims extracted using Large Language Models (LLMs). Additionally, we apply a semi-automated validation framework to enhance dataset reliability.Our analysis reveals that inherent dataset characteristics impact data properties, evidence retrieval, and AFC model performance. While enrichment generally improves detection, its efficacy varies, influenced by challenges such as self-reinforcing online misinformation and API limitations. This work contributes enriched datasets, associating original texts with retrieved evidence and LLM-extracted claims, to foster future evidence-based fact-checking research.The code and enriched data for this study is available at https://github.com/ju-resplande/pt_afc.
Anthology ID:
2025.fever-1.3
Volume:
Proceedings of the Eighth Fact Extraction and VERification Workshop (FEVER)
Month:
July
Year:
2025
Address:
Vienna, Austria
Editors:
Mubashara Akhtar, Rami Aly, Christos Christodoulopoulos, Oana Cocarascu, Zhijiang Guo, Arpit Mittal, Michael Schlichtkrull, James Thorne, Andreas Vlachos
Venues:
FEVER | WS
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
34–53
Language:
URL:
https://preview.aclanthology.org/landing_page/2025.fever-1.3/
DOI:
Bibkey:
Cite (ACL):
Juliana Gomes, Eduardo Garcia, and Arlindo Rodrigues Galvão Filho. 2025. Portuguese Automated Fact-checking: Information Retrieval with Claim extraction. In Proceedings of the Eighth Fact Extraction and VERification Workshop (FEVER), pages 34–53, Vienna, Austria. Association for Computational Linguistics.
Cite (Informal):
Portuguese Automated Fact-checking: Information Retrieval with Claim extraction (Gomes et al., FEVER 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/landing_page/2025.fever-1.3.pdf