English
Related papers

Related papers: Contrast to Detect: Dynamic Graph Contrastive Regu…

200 papers

Cross-domain graph anomaly detection (CD-GAD) describes the problem of detecting anomalous nodes in an unlabelled target graph using auxiliary, related source graphs with labelled anomalous and normal nodes. Although it presents a promising…

Machine Learning · Computer Science 2022-12-05 Qizhou Wang , Guansong Pang , Mahsa Salehi , Wray Buntine , Christopher Leckie

Among various region embedding methods, graph-based region relation learning models stand out, owing to their strong structure representation ability for encoding spatial correlations with graph neural networks. Despite their effectiveness,…

Machine Learning · Computer Science 2023-05-09 Qianru Zhang , Chao Huang , Lianghao Xia , Zheng Wang , Zhonghang Li , Siuming Yiu

Dynamic graph anomaly detection (DGAD) is critical for many real-world applications but remains challenging due to the scarcity of labeled anomalies. Existing methods are either unsupervised or semi-supervised: unsupervised methods avoid…

Machine Learning · Computer Science 2026-02-24 Yuxing Tian , Yiyan Qi , Fengran Mo , Weixu Zhang , Jian Guo , Jian-Yun Nie

Multivariate time series anomaly detection has become increasingly important in real-world applications, where labeled data are often scarce. Many existing approaches rely on unsupervised learning to model normal patterns, but they often…

Machine Learning · Computer Science 2026-05-25 Jaehyeop Hong , Youngbum Hur

We present a unified experiment, analysis, and benchmark study of multivariate time-series (MTS) anomaly detection. Ten family-representative detectors -- spanning statistical, reconstruction, association, frequency, and generic-transformer…

Machine Learning · Computer Science 2026-05-28 Junhao Wei , Yanxiao Li , Bidong Chen , Yifu Zhao , Haochen Li , Dexing Yao , Baili Lu , Xudong Ye , Jietian Feng , Sio-Kei Im , Yapeng Wang , Xu Yang

There have been several recent efforts towards developing representations for multivariate time-series in an unsupervised learning framework. Such representations can prove beneficial in tasks such as activity recognition, health…

Machine Learning · Computer Science 2022-09-23 Yitian Zhang , Florence Regol , Antonios Valkanas , Mark Coates

Time-series anomaly detection (TSAD) is a critical component in monitoring complex systems, yet modern deep learning-based detectors are often highly sensitive to localized input corruptions and structured noise. We propose ARTA…

Machine Learning · Computer Science 2026-05-07 Hadi Hojjati , Narges Armanfard

As a fundamental data mining task, unsupervised time series anomaly detection (TSAD) aims to build a model for identifying abnormal timestamps without assuming the availability of annotations. A key challenge in unsupervised TSAD is that…

Machine Learning · Computer Science 2026-02-10 Dezheng Wang , Tong Chen , Guansong Pang , Congyan Chen , Shihua Li , Hongzhi Yin

Nowadays, multivariate time series data are increasingly collected in various real world systems, e.g., power plants, wearable devices, etc. Anomaly detection and diagnosis in multivariate time series refer to identifying abnormal status in…

This paper addresses the challenges of complex dependencies and diverse anomaly patterns in cloud service environments by proposing a dependency modeling and anomaly detection method that integrates contrastive learning. The method…

Machine Learning · Computer Science 2025-10-16 Yue Xing , Yingnan Deng , Heyao Liu , Ming Wang , Yun Zi , Xiaoxuan Sun

Temporal graph representation learning aims to generate low-dimensional dynamic node embeddings to capture temporal information as well as structural and property information. Current representation learning methods for temporal networks…

Machine Learning · Computer Science 2023-11-08 Hongjiang Chen , Pengfei Jiao , Huijun Tang , Huaming Wu

Multimodal time series (MTS) anomaly detection is crucial for maintaining the safety and stability of working devices (e.g., water treatment system and spacecraft), whose data are characterized by multivariate time series with diverse…

Machine Learning · Computer Science 2023-10-18 Chaoyue Ding , Shiliang Sun , Jing Zhao

In this paper, we study the problem of unsupervised graph representation learning by harnessing the control properties of dynamical networks defined on graphs. Our approach introduces a novel framework for contrastive learning, a widely…

Machine Learning · Computer Science 2024-04-19 Obaid Ullah Ahmad , Anwar Said , Mudassir Shabbir , Waseem Abbas , Xenofon Koutsoukos

Graph anomaly detection aims to identify abnormal patterns in networks, but faces significant challenges from label scarcity and extreme class imbalance. While graph contrastive learning offers a promising unsupervised solution, existing…

Machine Learning · Computer Science 2026-01-30 Kamal Berahmand , Saman Forouzandeh , Mehrnoush Mohammadi , Parham Moradi , Mahdi Jalili

The rich information underlying graphs has inspired further investigation of unsupervised graph representation. Existing studies mainly depend on node features and topological properties within static graphs to create self-supervised…

Machine Learning · Computer Science 2026-05-27 Yiming Xu , Zhen Peng , Bin Shi , Xu Hua , Bo Dong

The core challenge in unsupervised anomaly detection is identifying abnormal patterns without prior knowledge of their characteristics. While existing methods have addressed aspects of this problem, they often struggle to learn a robust…

Machine Learning · Computer Science 2026-05-12 Prithul Sarker , Sushmita Sarker , Nicholas G. Murray , Alireza Tavakkoli

In the anomaly detection field, the scarcity of anomalous samples has directed the current research emphasis towards unsupervised anomaly detection. While these unsupervised anomaly detection methods offer convenience, they also overlook…

Information Retrieval · Computer Science 2023-11-15 Shunfeng Wang , Yueyang Li , Haichi Luo , Chenyang Bi

With the rapid growth of graph-structured data in critical domains, unsupervised graph-level anomaly detection (UGAD) has become a pivotal task. UGAD seeks to identify entire graphs that deviate from normal behavioral patterns. However,…

Machine Learning · Computer Science 2025-11-07 Qingfeng Chen , Haojin Zeng , Jingyi Jie , Shichao Zhang , Debo Cheng

Efficient anomaly detection and diagnosis in multivariate time-series data is of great importance for modern industrial applications. However, building a system that is able to quickly and accurately pinpoint anomalous observations is a…

Machine Learning · Computer Science 2022-05-17 Shreshth Tuli , Giuliano Casale , Nicholas R. Jennings

Anomaly detection aims to distinguish abnormal instances that deviate significantly from the majority of benign ones. As instances that appear in the real world are naturally connected and can be represented with graphs, graph neural…

Machine Learning · Computer Science 2023-05-24 Sheng Tian , Jihai Dong , Jintang Li , Wenlong Zhao , Xiaolong Xu , Baokun wang , Bowen Song , Changhua Meng , Tianyi Zhang , Liang Chen