RAcQUEt: Unveiling the Dangers of Overlooked Referential Ambiguity in Visual LLMs

Alberto Testoni, Barbara Plank, Raquel Fernández


Abstract
Ambiguity resolution is key to effective communication. While humans effortlessly address ambiguity through conversational grounding strategies, the extent to which current language models can emulate these strategies remains unclear. In this work, we examine referential ambiguity in image-based question answering by introducing RAcQUEt, a carefully curated dataset targeting distinct aspects of ambiguity. Through a series of evaluations, we reveal significant limitations and problems of overconfidence of state-of-the-art large multimodal language models in addressing ambiguity in their responses. The overconfidence issue becomes particularly relevant for RAcQUEt-BIAS, a subset designed to analyze a critical yet underexplored problem: failing to address ambiguity leads to stereotypical, socially biased responses. Our results underscore the urgency of equipping models with robust strategies to deal with uncertainty without resorting to undesirable stereotypes.
Anthology ID:
2025.emnlp-main.1206
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
EMNLP
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Publisher:
Association for Computational Linguistics
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Pages:
23638–23658
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URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.1206/
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Cite (ACL):
Alberto Testoni, Barbara Plank, and Raquel Fernández. 2025. RAcQUEt: Unveiling the Dangers of Overlooked Referential Ambiguity in Visual LLMs. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 23638–23658, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
RAcQUEt: Unveiling the Dangers of Overlooked Referential Ambiguity in Visual LLMs (Testoni et al., EMNLP 2025)
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https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.1206.pdf
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