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arXiv · 2302.06048

Unsupervised Deep One-Class Classification with Adaptive Threshold based on Training Dynamics

Minkyung Kim·Junsik Kim·Jongmin Yu·Jun Kyun Choi
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Abstract

One-class classification has been a prevailing method in building deep anomaly detection models under the assumption that a dataset consisting of normal samples is available. In practice, however, abnormal samples are often mixed in a training dataset, and they detrimentally affect the training of deep models, which limits their applicability. For robust normality learning of deep practical models, we propose an unsupervised deep one-class classification that learns normality from pseudo-labeled normal samples, i.e., outlier detection in single cluster scenarios. To this end, we propose a pseudo-labeling method by an adaptive threshold selected by ranking-based training dynamics. The experiments on 10 anomaly detection benchmarks show that our method effectively improves performance on anomaly detection by sizable margins.

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Minkyung Kim, Junsik Kim, Jongmin Yu, Jun Kyun Choi. 2023-02-13. Unsupervised Deep One-Class Classification with Adaptive Threshold based on Training Dynamics. https://doi.org/10.1109/icdmw58026.2022.00014

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