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Related papers: Graph Contrastive Learning for Anomaly Detection

200 papers

Graph-level anomaly detection (GLAD) has already gained significant importance and has become a popular field of study, attracting considerable attention across numerous downstream works. The core focus of this domain is to capture and…

Machine Learning · Computer Science 2024-07-17 Zitong Wang , Xuexiong Luo , Enfeng Song , Qiuqing Bai , Fu Lin

Graph machine learning has been widely explored in various domains, such as community detection, transaction analysis, and recommendation systems. In these applications, anomaly detection plays an important role. Recently, studies have…

Machine Learning · Computer Science 2025-11-21 Wei Herng Choong , Jixing Liu , Ching-Yu Kao , Philip Sperl

Graph contrastive learning is the state-of-the-art unsupervised graph representation learning framework and has shown comparable performance with supervised approaches. However, evaluating whether the graph contrastive learning is robust to…

Machine Learning · Computer Science 2022-01-28 Sixiao Zhang , Hongxu Chen , Xiangguo Sun , Yicong Li , Guandong Xu

Different from the current node-level anomaly detection task, the goal of graph-level anomaly detection is to find abnormal graphs that significantly differ from others in a graph set. Due to the scarcity of research on the work of…

Machine Learning · Computer Science 2023-08-07 Fu Lin , Xuexiong Luo , Jia Wu , Jian Yang , Shan Xue , Zitong Wang , Haonan Gong

Graphs are present in many real-world applications, such as financial fraud detection, commercial recommendation, and social network analysis. But given the high cost of graph annotation or labeling, we face a severe graph label-scarcity…

Machine Learning · Computer Science 2022-08-08 Zhen Tan , Kaize Ding , Ruocheng Guo , Huan Liu

Weakly supervised graph anomaly detection aims to unveil unusual graph instances, e.g., nodes, whose behaviors significantly differ from normal ones, given only a limited number of annotated anomalies and abundant unlabeled samples. A major…

Machine Learning · Computer Science 2026-05-13 Yingjie Zhou , Yuqin Xie , Fanxing Liu , Dongjin Song , Ce Zhu , Lingqiao Liu

Unsupervised GAD methods assume the lack of anomaly labels, i.e., whether a node is anomalous or not. One common observation we made from previous unsupervised methods is that they not only assume the absence of such anomaly labels, but…

Machine Learning · Computer Science 2023-08-24 Junghoon Kim , Yeonjun In , Kanghoon Yoon , Junmo Lee , Chanyoung Park

Graph representation learning nowadays becomes fundamental in analyzing graph-structured data. Inspired by recent success of contrastive methods, in this paper, we propose a novel framework for unsupervised graph representation learning by…

Machine Learning · Computer Science 2020-07-14 Yanqiao Zhu , Yichen Xu , Feng Yu , Qiang Liu , Shu Wu , Liang Wang

Unsupervised graph anomaly detection aims at identifying rare patterns that deviate from the majority in a graph without the aid of labels, which is important for a variety of real-world applications. Recent advances have utilized Graph…

Machine Learning · Computer Science 2025-05-27 Yuanchen Bei , Sheng Zhou , Jinke Shi , Yao Ma , Haishuai Wang , Jiajun Bu

Anomaly detection using a network-based approach is one of the most efficient ways to identify abnormal events such as fraud, security breaches, and system faults in a variety of applied domains. While most of the earlier works address the…

Artificial Intelligence · Computer Science 2025-01-22 Hossein Rafieizadeh , Hadi Zare , Mohsen Ghassemi Parsa , Hadi Davardoust , Meshkat Shariat Bagheri

Recently, contrastive learning (CL) has emerged as a successful method for unsupervised graph representation learning. Most graph CL methods first perform stochastic augmentation on the input graph to obtain two graph views and maximize the…

Machine Learning · Computer Science 2021-03-01 Yanqiao Zhu , Yichen Xu , Feng Yu , Qiang Liu , Shu Wu , Liang Wang

Graph Neural Networks (GNNs) are widely used as the engine for various graph-related tasks, with their effectiveness in analyzing graph-structured data. However, training robust GNNs often demands abundant labeled data, which is a critical…

Machine Learning · Computer Science 2025-09-16 Siyue Xie , Da Sun Handason Tam , Wing Cheong Lau

We develop graph-based methods for semi-supervised learning based on label propagation on a data similarity graph. When data is abundant or arrive in a stream, the problems of computation and data storage arise for any graph-based method.…

Machine Learning · Computer Science 2026-05-06 Michal Valko

Graph anomaly detection has attracted a lot of interest recently. Despite their successes, existing detectors have at least two of the three weaknesses: (a) high computational cost which limits them to small-scale networks only; (b)…

Machine Learning · Computer Science 2023-01-18 Zhong Zhuang , Kai Ming Ting , Guansong Pang , Shuaibin Song

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

Graph Neural Networks (GNNs) have achieved great success in learning graph representations and thus facilitating various graph-related tasks. However, most GNN methods adopt a supervised learning setting, which is not always feasible in…

Machine Learning · Computer Science 2022-08-16 Hongliang Chi , Yao Ma

Anomaly detection is a ubiquitous and challenging task relevant across many disciplines. With the vital role communication networks play in our daily lives, the security of these networks is imperative for smooth functioning of society. To…

Cryptography and Security · Computer Science 2022-10-18 Gopikrishna Rathinavel , Nikhil Muralidhar , Timothy O'Shea , Naren Ramakrishnan

Graphs are used widely to model complex systems, and detecting anomalies in a graph is an important task in the analysis of complex systems. Graph anomalies are patterns in a graph that do not conform to normal patterns expected of the…

Machine Learning · Computer Science 2022-10-05 Hwan Kim , Byung Suk Lee , Won-Yong Shin , Sungsu Lim

Graph representation learning has attracted a surge of interest recently, whose target at learning discriminant embedding for each node in the graph. Most of these representation methods focus on supervised learning and heavily depend on…

Machine Learning · Computer Science 2021-07-07 Pengpeng Shao , Tong Liu , Dawei Zhang , Jianhua Tao , Feihu Che , Guohua Yang

A graph-based sampling and consensus (GraphSAC) approach is introduced to effectively detect anomalous nodes in large-scale graphs. Existing approaches rely on connectivity and attributes of all nodes to assign an anomaly score per node.…

Machine Learning · Computer Science 2019-10-23 Vassilis N. Ioannidis , Dimitris Berberidis , Georgios B. Giannakis