The influence of visual and linguistic cues on ignorance inference in Vision-Language Models (VLMs)

This study explored how Vision-Language Models (VLMs) process ignorance implicatures with visual and linguistic cues. Particularly, we focused on the effects of contexts (precise and approximate contexts) and modifier types (bare numerals, superlative, and comparative modifiers), which were considered pragmatic and semantic factors respectively. Methodologically, we conducted a truth-value judgment task in visually grounded settings using GPT-4o and Gemini 1.5 Pro. The results indicate that while both models exhibited sensitivity to linguistic cues (modifier), they failed to process ignorance implicatures with visual cues (context) as humans do. Specifically, the influence of context was weaker and inconsistent across models, indicating challenges in pragmatic reasoning for VLMs. On the other hand, superlative modifiers were more strongly associated with ignorance implicatures as compared to comparative modifiers, supporting the semantic view. These findings highlight the need for further advancements in VLMs to process language-vision information in a context-dependent way to achieve human-like pragmatic inference.