Probabilistic Contrastive Loss for Self-Supervised Learning

Shen Li; Jianqing Xu; Bryan Hooi

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arXiv · 2112.01642

Probabilistic Contrastive Loss for Self-Supervised Learning

Shen Li·Jianqing Xu·Bryan Hooi

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Abstract

This paper proposes a probabilistic contrastive loss function for self-supervised learning. The well-known contrastive loss is deterministic and involves a temperature hyperparameter that scales the inner product between two normed feature embeddings. By reinterpreting the temperature hyperparameter as a quantity related to the radius of the hypersphere, we derive a new loss function that involves a confidence measure which quantifies uncertainty in a mathematically grounding manner. Some intriguing properties of the proposed loss function are empirically demonstrated, which agree with human-like predictions. We believe the present work brings up a new prospective to the area of contrastive learning.

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BibTeX RIS

Shen Li, Jianqing Xu, Bryan Hooi. 2021-12-02. Probabilistic Contrastive Loss for Self-Supervised Learning. https://arxiv.org/abs/2112.01642

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