Community-Centric Graph Unlearning

TL;DR

This paper introduces a novel community-centric graph unlearning method that efficiently eliminates specific data effects in GNNs by leveraging community structure mapping, reducing data and parameter requirements significantly.

Contribution

It proposes the GSMU paradigm and the CGE method, which utilize community mapping to improve unlearning efficiency and effectiveness in graph neural networks.

Findings

CGE achieves high performance on real-world datasets.

CGE significantly reduces training data and unlearning parameters.

Experiments validate the efficiency and effectiveness of the proposed method.

Abstract

Graph unlearning technology has become increasingly important since the advent of the `right to be forgotten' and the growing concerns about the privacy and security of artificial intelligence. Graph unlearning aims to quickly eliminate the effects of specific data on graph neural networks (GNNs). However, most existing deterministic graph unlearning frameworks follow a balanced partition-submodel training-aggregation paradigm, resulting in a lack of structural information between subgraph neighborhoods and redundant unlearning parameter calculations. To address this issue, we propose a novel Graph Structure Mapping Unlearning paradigm (GSMU) and a novel method based on it named Community-centric Graph Eraser (CGE). CGE maps community subgraphs to nodes, thereby enabling the reconstruction of a node-level unlearning operation within a reduced mapped graph. CGE makes the exponential reduction of both the amount of training data and the number of unlearning parameters. Extensive experiments conducted on five real-world datasets and three widely used GNN backbones have verified the high performance and efficiency of our CGE method, highlighting its potential in the field of graph unlearning.