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This content will become publicly available on April 25, 2023

Title: Graph Sanitation with Application to Node Classification
The past decades have witnessed the prosperity of graph mining, with a multitude of sophisticated models and algorithms designed for various mining tasks, such as ranking, classification, clustering and anomaly detection. Generally speaking, the vast majority of the existing works aim to answer the following question, that is, given a graph, what is the best way to mine it? In this paper, we introduce the graph sanitation problem, to an- swer an orthogonal question. That is, given a mining task and an initial graph, what is the best way to improve the initially provided graph? By learning a better graph as part of the input of the mining model, it is expected to benefit graph mining in a variety of settings, ranging from denoising, imputation to defense. We formulate the graph sanitation problem as a bilevel optimization problem, and fur- ther instantiate it by semi-supervised node classification, together with an effective solver named GaSoliNe. Extensive experimental results demonstrate that the proposed method is (1) broadly appli- cable with respect to various graph neural network models and flexible graph modification strategies, (2) effective in improving the node classification accuracy on both the original and contaminated graphs in various perturbation scenarios. In particular, more » it brings up to 25% performance improvement over the existing robust graph neural network methods. « less
Authors:
; ;
Award ID(s):
1947135 2134079
Publication Date:
NSF-PAR ID:
10332504
Journal Name:
Graph Sanitation with Application to Node Classification
Page Range or eLocation-ID:
1136 to 1147
Sponsoring Org:
National Science Foundation
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