Black Sheep in the Herd: Playing with Spuriously Correlated Attributes for Vision-Language Recognition

Few-shot adaptation for Vision-Language Models (VLMs) presents a dilemma: balancing in-distribution accuracy with out-of-distribution generalization. Recent research has utilized low-level concepts such as visual attributes to enhance generalization. However, this study reveals that VLMs overly rely on a small subset of attributes on decision-making, which co-occur with the category but are not inherently part of it, termed spuriously correlated attributes. This biased nature of VLMs results in poor generalization. To address this, 1) we first propose SPURI-OUS ATTRIBUTE PROBING (SAP), identifying and filtering out these problematic attributes to significantly enhance the generalization of existing attribute-based methods; 2) We introduce SPURIOUS ATTRIBUTE SHIELDING (SAS), a plugand-play module that mitigates the influence of these attributes, seamlessly integrating into various Parameter-Efficient Fine-Tuning (PEFT) methods. In experiments, SAP and SAS significantly enhance accuracy on distribution shifts across 11 datasets and 3 generalization tasks while preserving downstream performance, establishing a new state-of-the-art benchmark. The code will be available here.