Unified Framework for Feature Extraction based on Contrastive Learning
This work addresses feature extraction for machine learning practitioners dealing with high-dimensional data, but it appears incremental as it builds on existing contrastive learning approaches.
The authors tackled the problem of feature extraction for high-dimensional data by proposing a unified framework based on contrastive learning that works for both unsupervised and supervised settings, and demonstrated superior performance on five real datasets compared to existing methods.
Feature extraction is an efficient approach for alleviating the issue of dimensionality in high-dimensional data. As a popular self-supervised learning method, contrastive learning has recently garnered considerable attention. In this study, we proposed a unified framework based on a new perspective of contrastive learning (CL) that is suitable for both unsupervised and supervised feature extraction. The proposed framework first constructed two CL graph for uniquely defining the positive and negative pairs. Subsequently, the projection matrix was determined by minimizing the contrastive loss function. In addition, the proposed framework considered both similar and dissimilar samples to unify unsupervised and supervised feature extraction. Moreover, we propose the three specific methods: unsupervised contrastive learning method, supervised contrastive learning method 1 ,and supervised contrastive learning method 2. Finally, the numerical experiments on five real datasets demonstrated the superior performance of the proposed framework in comparison to the existing methods.