Title
Decoupling Representation Learning and Classification for GNN-based Anomaly Detection
Abstract
ABSTRACTGNN-based anomaly detection has recently attracted considerable attention. Existing attempts have thus far focused on jointly learning the node representations and the classifier for detecting the anomalies. Inspired by the recent advances of self-supervised learning (SSL) on graphs, we explore another possibility of decoupling the node representation learning and the classification for anomaly detection. We conduct a preliminary study to show that decoupled training using existing graph SSL schemes to represent nodes can obtain performance gains over joint training, but it may deteriorate when the behavior patterns and the label semantics become highly inconsistent. To be less biased by the inconsistency, we propose a simple yet effective graph SSL scheme, called Deep Cluster Infomax (DCI) for node representation learning, which captures the intrinsic graph properties in more concentrated feature spaces by clustering the entire graph into multiple parts. We conduct extensive experiments on four real-world datasets for anomaly detection. The results demonstrate that decoupled training equipped with a proper SSL scheme can outperform joint training in AUC. Compared with existing graph SSL schemes, DCI can help decoupled training gain more improvements.
Year
DOI
Venue
2021
10.1145/3404835.3462944
IR
Keywords
DocType
Citations 
anomaly detection, graph neural network, decoupled training, selfsupervised learning
Conference
1
PageRank 
References 
Authors
0.35
30
6
Name
Order
Citations
PageRank
Yan-Ling Wang12414.44
Jing Zhang2128155.47
Shasha Guo310.35
Hongzhi Yin42511.92
Cuiping Li5399.19
Hong Chen6259.84