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arXiv · 2310.11676

PREM: A Simple Yet Effective Approach for Node-Level Graph Anomaly Detection

Junjun Pan·Yixin Liu·Yizhen Zheng·Shirui Pan
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Abstract

Node-level graph anomaly detection (GAD) plays a critical role in identifying anomalous nodes from graph-structured data in various domains such as medicine, social networks, and e-commerce. However, challenges have arisen due to the diversity of anomalies and the dearth of labeled data. Existing methodologies - reconstruction-based and contrastive learning - while effective, often suffer from efficiency issues, stemming from their complex objectives and elaborate modules. To improve the efficiency of GAD, we introduce a simple method termed PREprocessing and Matching (PREM for short). Our approach streamlines GAD, reducing time and memory consumption while maintaining powerful anomaly detection capabilities. Comprising two modules - a pre-processing module and an ego-neighbor matching module - PREM eliminates the necessity for message-passing propagation during training, and employs a simple contrastive loss, leading to considerable reductions in training time and memory usage. Moreover, through rigorous evaluations of five real-world datasets, our method demonstrated robustness and effectiveness. Notably, when validated on the ACM dataset, PREM achieved a 5% improvement in AUC, a 9-fold increase in training speed, and sharply reduce memory usage compared to the most efficient baseline.

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Junjun Pan, Yixin Liu, Yizhen Zheng, Shirui Pan. 2023-10-18. PREM: A Simple Yet Effective Approach for Node-Level Graph Anomaly Detection. https://arxiv.org/abs/2310.11676

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