Title
SORAG: Synthetic Data Over-Sampling Strategy on Multi-Label Graphs
Abstract
In many real-world networks of interest in the field of remote sensing (e.g., public transport networks), nodes are associated with multiple labels, and node classes are imbalanced; that is, some classes have significantly fewer samples than others. However, the research problem of imbalanced multi-label graph node classification remains unexplored. This non-trivial task challenges the existing graph neural networks (GNNs) because the majority class can dominate the loss functions of GNNs and result in the overfitting of the majority class features and label correlations. On non-graph data, minority over-sampling methods (such as the synthetic minority over-sampling technique and its variants) have been demonstrated to be effective for the imbalanced data classification problem. This study proposes and validates a new hypothesis with unlabeled data over-sampling, which is meaningless for imbalanced non-graph data; however, feature propagation and topological interplay mechanisms between graph nodes can facilitate the representation learning of imbalanced graphs. Furthermore, we determine empirically that ensemble data synthesis through the creation of virtual minority samples in the central region of a minority and generation of virtual unlabeled samples in the boundary region between a minority and majority is the best practice for the imbalanced multi-label graph node classification task. Our proposed novel data over-sampling framework is evaluated using multiple real-world network datasets, and it outperforms diverse, strong benchmark models by a large margin.
Year
DOI
Venue
2022
10.3390/rs14184479
REMOTE SENSING
Keywords
DocType
Volume
imbalanced data classification, data over-sampling, generative adversarial network, graph convolutional network, semi-supervised learning, remote sensing
Journal
14
Issue
ISSN
Citations 
18
2072-4292
0
PageRank 
References 
Authors
0.34
0
7
Name
Order
Citations
PageRank
Yijun Duan100.34
Xin Liu23919320.56
Adam Jatowt3903106.73
Hai-tao Yu400.68
Steven Lynden500.34
Kyoung-Sook Kim600.34
Akiyoshi Matono700.34