Learning the feature distribution similarities for online time series anomaly detection
Jin Fan1, Yan Ge2, Xinyi Zhang2
1Department of Computer Science and Technology, Hangzhou Dianzi University, Hangzhou, China; Zhejiang Provincial Key Laboratory of Industrial Internet in Discrete Industries, Hangzhou Dianzi University, Hangzhou, China.
Summary
SimDetector enhances anomaly detection in multi-dimensional sequential data by contrasting local and global features. This efficient framework improves accuracy and interpretability while reducing computational costs.
Area of Science:
- Data Science
- Machine Learning
- Artificial Intelligence
Background:
- Anomaly detection in multi-dimensional sequential data is vital for system performance.
- Traditional contrastive methods face challenges in efficiency and interpretability.
- Existing methods often struggle with complex objective functions and module design.
Purpose of the Study:
- Introduce SimDetector, a novel Local-Global Multi-Scale Similarity Contrast network.
- Improve efficiency and interpretability in anomaly detection.
- Address limitations of current contrastive learning approaches.
Main Methods:
- Utilize a restructured GRU module for generalized local feature extraction, capturing long-term trends.
- Employ a multi-scale sparse attention module for efficient global feature extraction with pattern information.
- Propose a symmetric absolute KL divergence tailored for time series anomaly detection, emphasizing distribution differences.
Main Results:
- SimDetector achieves state-of-the-art or competitive results on real-world and synthetic datasets.
- Significantly reduces Multiply-Accumulate Operations (MACs) and memory usage compared to existing methods.
- Demonstrates improved accuracy and efficiency in identifying anomalies.
Conclusions:
- SimDetector offers an effective and efficient solution for anomaly detection in multi-dimensional sequential data.
- The proposed framework balances performance with reduced computational overhead.
- Highlights the potential of multi-scale similarity contrast for complex data analysis.
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