This study proposes a novel approach for solving the PU learning problem based on an anomaly-detection strategy. Latent encodings extracted from positive-labeled data are linearly combined to acquire new samples. These new samples are used as embeddings to increase the density of positive-labeled data and, thus, define a boundary that approximates the positive class. The further a sample is from the boundary the more it is considered as a negative sample. Once a set of negative samples is obtained, the PU learning problem reduces to binary classification. The approach, named Dens-PU due to its reliance on the density of positive-labeled data, was evaluated using benchmark image datasets, and state-of-the-art results were attained.
@article{arxiv.2303.11848,
title = {Dens-PU: PU Learning with Density-Based Positive Labeled Augmentation},
author = {Vasileios Sevetlidis and George Pavlidis and Spyridon Mouroutsos and Antonios Gasteratos},
journal= {arXiv preprint arXiv:2303.11848},
year = {2024}
}