The Art of Saying "Maybe": A Conformal Lens for Uncertainty Benchmarking in VLMs
On the map: Multimodal LLMs / vision-language models → Hallucination mitigation in LVLMs
Abstract (arXiv)
Vision-Language Models (VLMs) have achieved remarkable progress in complex visual understanding across scientific and reasoning tasks. While performance benchmarking has advanced our understanding of these capabilities, the critical dimension of uncertainty quantification has received insufficient attention. Therefore, unlike prior conformal prediction studies that focused on limited settings, we conduct a comprehensive uncertainty benchmarking study, evaluating 18 state-of-the-art VLMs (open and closed-source) across 6 multimodal datasets with 3 distinct scoring functions. For closed-source models lacking token-level logprob access, we develop and validate instruction-guided likelihood proxies. Our findings demonstrate that larger models consistently exhibit better uncertainty quantification; models that know more also know better what they don't know. More certain models achieve higher accuracy, while mathematical and reasoning tasks elicit poorer uncertainty performance across all models compared to other domains. This work establishes a foundation for reliable uncertainty evaluation in multimodal systems.
Key facts. Cited by 2 papers in the map (data through 14 Oct 2026). Placed in Hallucination mitigation in LVLMs, one of 16 directions in Multimodal LLMs / vision-language models. Builds on 22 of its 37 references that are in the map. First posted on arXiv 16 Sep 2025.
Builds on
22 of 37 references.
References · 22
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10 more
- 2024Measuring Multimodal Mathematical Reasoning with MATH-Vision Datasetcited by 526
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Citing papers per year: 2026: 2.
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- 2024Uncertainty-Aware Evaluation for Vision-Language Models
- 2025Seeing is Believing, but How Much? A Comprehensive Analysis of Verbalized Calibration in Vision-Language Models
- 2026VLM-UQBench: A Benchmark for Modality-Specific and Cross-Modality Uncertainties in Vision Language Models
- 2026VAUQ: Vision-Aware Uncertainty Quantification for LVLM Self-Evaluation
- 2026Leveraging Visual Signals for Robust Token-Level Uncertainty in Vision-Language Generation
- 2026FUSE: Quantifying Uncertainty in Vision-Language Models by Bayesian Fusing Epistemic and Aleatoric Uncertainty
- 2024Unveiling Uncertainty: A Deep Dive into Calibration and Performance of Multimodal Large Language Models
- 2025Exploiting the Asymmetric Uncertainty Structure of Pre-trained VLMs on the Unit Hypersphere