Publication Type
Conference Proceeding Article
Version
publishedVersion
Publication Date
10-2023
Abstract
Anomaly detection (AD) is a crucial machine learning task that aims to learn patterns from a set of normal training samples to identify abnormal samples in test data. Most existing AD studies assume that the training and test data are drawn from the same data distribution, but the test data can have large distribution shifts arising in many real-world applications due to different natural variations such as new lighting conditions, object poses, or background appearances, rendering existing AD methods ineffective in such cases. In this paper, we consider the problem of anomaly detection under distribution shift and establish performance benchmarks on four widely-used AD and out-of-distribution (OOD) generalization datasets. We demonstrate that simple adaptation of state-of-the-art OOD generalization methods to AD settings fails to work effectively due to the lack of labeled anomaly data. We further introduce a novel robust AD approach to diverse distribution shifts by minimizing the distribution gap between indistribution and OOD normal samples in both the training and inference stages in an unsupervised way. Our extensive empirical results on the four datasets show that our approach substantially outperforms state-of-the-art AD methods and OOD generalization methods on data with various distribution shifts, while maintaining the detection accuracy on in-distribution data. Code and data are available at https://github.com/mala-lab/ADShift.
Discipline
Databases and Information Systems
Research Areas
Data Science and Engineering
Publication
Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV), Paris, France, October 2-6
First Page
6551
Last Page
6523
Publisher
IEEE
City or Country
Piscataway, NJ
Citation
CAO, Tri; ZHU, Jiawen; and PANG, Guansong.
Anomaly detection under distribution shift. (2023). Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV), Paris, France, October 2-6. 6551-6523.
Available at: https://ink.library.smu.edu.sg/sis_research/8415
Copyright Owner and License
Authors
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.