arXiv Machine Learning

Divergence-Based Similarity Function for Multi-View Contrastive Learning

The paper introduces a divergence-based similarity function (DSF) for multi-view contrastive learning, representing each set of augmented views as a distribution and measuring similarity via distribution divergence. DSF captures joint structure across all views, outperforming prior pairwise methods on tasks such as kNN classification, linear evaluation, transfer learning, and distribution shift. It also offers greater efficiency and eliminates the need for a temperature hyperparameter, unlike cosine similarity.

arXiv AI
Oct 7

Anchor Divergence for Semantic Geometry in Contrastive Learning

The paper introduces Anchor Divergences, a technique that leverages contrastive learning, exponential families, and information geometry to define context‑specific semantic geometries on fixed vector representations. By establishing a correspondence between probability distributions over anchors and Bregman geometries, the method allows the geometry itself to be modeled through the anchor distribution. Experiments on retrieval tasks demonstrate that Anchor Divergences effectively and efficiently capture context‑dependent semantic similarity.

By Akash Kannan, Kiho Park, Victor Veitch
arXiv AI
Oct 26

Rethinking Representation Geometry in Supervised Contrastive Learning under Long-Tailed Data

The paper investigates whether supervised contrastive learning objectives produce a regular simplex geometry in representation space when trained on long‑tailed data. It shows that existing objectives fail to achieve this geometry because they depend on class sample counts. The authors propose a fully balanced contrastive objective that provably forms a regular simplex, leading to a more balanced representation space and improved performance on long‑tailed recognition and transfer learning tasks.

By Joonhyeok Jeong, Jy-yong Sohn, Kibok Lee
arXiv Computer Vision
Sep 11

Prototype Matters: Modality-unified Prototype Self-distillation for Unsupervised Visible-infrared Person Re-identification

The paper introduces a new framework for unsupervised visible‑infrared person re‑identification that leverages modality‑unified prototypes. By contrasting with prototypes that unify both modalities, the method jointly optimizes similarity within and across modalities, improving modality invariance. A self‑distillation step refines instance‑prototype relationships using a steady teacher, resulting in a simple yet effective model validated on standard VI‑ReID benchmarks.

By Menglin Wang, Xiaojin Gong
arXiv AI
Aug 20

From Inference to Adaptation: A Unified Optimal Transport View of Vision Language Model

arXiv:2608. 18339v1 Announce Type: cross Abstract: Vision-language models (VLMs) have demonstrated remarkable zero-shot capabilities yet remain sensitive to real-world distribution shifts during inference.

By Qi Yu, Zhichen Zeng, Katherine Tieu, Xiyuan Yang, Ruizhong Qiu, Yuchen Yan, Lihui Liu, Yanjun Zhao, Lingjie Chen, Jingrui He, Hanghang Tong
arXiv AI
Sep 18

Model Specific Task Similarity for Vision Language Model Selection via Layer Conductance

The paper introduces a method for selecting the best vision‑language model for a downstream task by analyzing the internal dynamics of the visual encoder. It represents each task with layer‑wise conductance and uses an entropy‑regularized alignment to derive a target‑conditioned block importance distribution. The proposed Directional Conductance Divergence (DCD) metric captures asymmetric transferability, enabling accurate prediction of model rankings without direct inference, and achieves a 14.7% NDCG@5 improvement over SWAB on 48 VLMs across 21 datasets.

By Wei Yang, Hong Xie, Tao Tan, Xin Li, Defu Lian, Enhong Chen