Unleashing the Potential of All Test Samples: Mean-Shift Guided Test-Time Adaptation
On the map: Multimodal LLMs / vision-language models → Prompt learning and adaptation of CLIP
Abstract (arXiv)
Visual-language models (VLMs) like CLIP exhibit strong generalization but struggle with distribution shifts at test time. Existing training-free test-time adaptation (TTA) methods operate strictly within CLIP's original feature space, relying on high-confidence samples while overlooking the potential of low-confidence ones. We propose MS-TTA, a training-free approach that enhances feature representations beyond CLIP's space using a single-step k-nearest neighbors (kNN) Mean-Shift. By refining all test samples, MS-TTA improves feature compactness and class separability, leading to more stable adaptation. Additionally, a cache of refined embeddings further enhances inference by providing Mean Shift enhanced logits. Extensive evaluations on OOD and cross-dataset benchmarks demonstrate that MS-TTA consistently outperforms state-of-the-art training-free TTA methods, achieving robust adaptation without requiring additional training.
Key facts. Cited by 1 paper in the map (data through 14 Oct 2026). Placed in Prompt learning and adaptation of CLIP, one of 16 directions in Multimodal LLMs / vision-language models. Builds on 46 of its 79 references that are in the map. First posted on arXiv 1 Jul 2025.
Builds on
46 of 79 references.
Closest ancestors · 13
Same direction, newest first
- 2025Beyond CLIP Generalization: Against Forward&Backward Forgetting Adapter for Continual Learning of Vision-Language Models12 May
- 2025Bayesian Test-Time Adaptation for Vision-Language Models12 Mar
- 2024BoostAdapter: Improving Vision-Language Test-Time Adaptation via Regional Bootstrapping20 Oct
- 2024Dual Prototype Evolving for Test-Time Generalization of Vision-Language Models16 Oct
- 2024DOTA: Distributional Test-Time Adaptation of Vision-Language Models28 Sep
- 2024On the test-time zero-shot generalization of vision-language models: Do we really need prompt learning?3 May
- 2024Efficient Test-Time Adaptation of Vision-Language Models27 Mar
- 2023Diverse Data Augmentation with Diffusions for Effective Test-time Prompt Tuning11 Aug
- 2022Test-Time Prompt Tuning for Zero-Shot Generalization in Vision-Language Models15 Sep
- 2022Tip-Adapter: Training-free Adaption of CLIP for Few-shot Classification19 Jul
- 2022Conditional Prompt Learning for Vision-Language Models10 Mar
- 2021Decoupling Zero-Shot Semantic Segmentation15 Dec
1 more
Other references · 33
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- 2019Learning Robust Global Representations by Penalizing Local Predictive Powercited by 1,013
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- 2021Class-agnostic Object Detection with Multi-modal Transformercited by 85
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Built on by
Citing papers per year: 2026: 1.
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