journal article·2023-01-30Open access

Is It Worth It? Comparing Six Deep and Classical Methods for Unsupervised Anomaly Detection in Time Series

Ferdinand Rewicki, Joachim Denzler, Julia Niebling

Applied Sciences· Volume 13· Issue 3

Abstract

Detecting anomalies in time series data is important in a variety of fields, including system monitoring, healthcare and cybersecurity. While the abundance of available methods makes it difficult to choose the most appropriate method for a given application, each method has its strengths in detecting certain types of anomalies. In this study, we compare six unsupervised anomaly detection methods of varying complexity to determine whether more complex methods generally perform better and if certain methods are better suited to certain types of anomalies. We evaluated the methods using the UCR anomaly archive, a recent benchmark dataset for anomaly detection. We analyzed the results on a dataset and anomaly-type level after adjusting the necessary hyperparameters for each method. Additionally, we assessed the ability of each method to incorporate prior knowledge about anomalies and examined the differences between point-wise and sequence-wise features. Our experiments show that classical machine learning methods generally outperform deep learning methods across a range of anomaly types.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Anomaly Detection Techniques and Applications · Network Security and Intrusion Detection · Time Series Analysis and Forecasting

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Institute of Data Science, German Aerospace Center, 07745 Jena, Germany

Faculty of Mathematics and Computer Science, Friedrich Schiller University, 07743 Jena, Germany

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