arXiv AI By Aditya Sharma, Divya Saxena

One Geometry, Different Outcomes: Readout-Dependent Effects of the Modality Gap in Vision-Language Models

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The paper investigates how the modality gap— the separation between image and text representations in contrastive vision‑language models—affects different downstream tasks. By showing that a single dominant direction accounts for most of the image‑text mean separation, the authors explain why reducing or removing this gap can improve zero‑shot classification, degrade retrieval, or restore performance depending on the task. The study provides a geometric framework that clarifies when and why gap interventions should be applied in vision‑language systems.

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