Table of Contents
Fetching ...

Graph Unlearning with Efficient Partial Retraining

Jiahao Zhang, Lin Wang, Shijie Wang, Wenqi Fan

TL;DR

The paper tackles unlearning in graph neural networks by addressing the limitations of existing retraining-based methods, which often degrade sub-model utility when partitions erode structural/semantic information. It introduces GraphRevoker, a two-part framework: (i) graph property-aware sharding that uses a differentiable partition network to create $S$ subgraphs while optimizing unlearning time, edge cuts via $Ncut$, and label distribution via entropy; and (ii) graph contrastive sub-model aggregation that ensembles sub-models with attentive fusion and a local-global contrastive loss together with a local-local reconstruction loss. The aggregation module, trained on a small labeled subset, yields strong predictive performance with efficient unlearning, and the whole approach fits within the retraining-based paradigm to guarantee exact removal of undesirable data. Extensive experiments on four real-world datasets show GraphRevoker outperforms existing efficient unlearning methods in both model utility and unlearning time, with ablations confirming the necessity of the partitioning and aggregation components. Overall, GraphRevoker offers a scalable, exact, and utility-preserving solution for graph unlearning in GNNs, enabling safe removal of undesirable data in large-scale graphs.

Abstract

Graph Neural Networks (GNNs) have achieved remarkable success in various real-world applications. However, GNNs may be trained on undesirable graph data, which can degrade their performance and reliability. To enable trained GNNs to efficiently unlearn unwanted data, a desirable solution is retraining-based graph unlearning, which partitions the training graph into subgraphs and trains sub-models on them, allowing fast unlearning through partial retraining. However, the graph partition process causes information loss in the training graph, resulting in the low model utility of sub-GNN models. In this paper, we propose GraphRevoker, a novel graph unlearning framework that better maintains the model utility of unlearnable GNNs. Specifically, we preserve the graph property with graph property-aware sharding and effectively aggregate the sub-GNN models for prediction with graph contrastive sub-model aggregation. We conduct extensive experiments to demonstrate the superiority of our proposed approach.

Graph Unlearning with Efficient Partial Retraining

TL;DR

The paper tackles unlearning in graph neural networks by addressing the limitations of existing retraining-based methods, which often degrade sub-model utility when partitions erode structural/semantic information. It introduces GraphRevoker, a two-part framework: (i) graph property-aware sharding that uses a differentiable partition network to create subgraphs while optimizing unlearning time, edge cuts via , and label distribution via entropy; and (ii) graph contrastive sub-model aggregation that ensembles sub-models with attentive fusion and a local-global contrastive loss together with a local-local reconstruction loss. The aggregation module, trained on a small labeled subset, yields strong predictive performance with efficient unlearning, and the whole approach fits within the retraining-based paradigm to guarantee exact removal of undesirable data. Extensive experiments on four real-world datasets show GraphRevoker outperforms existing efficient unlearning methods in both model utility and unlearning time, with ablations confirming the necessity of the partitioning and aggregation components. Overall, GraphRevoker offers a scalable, exact, and utility-preserving solution for graph unlearning in GNNs, enabling safe removal of undesirable data in large-scale graphs.

Abstract

Graph Neural Networks (GNNs) have achieved remarkable success in various real-world applications. However, GNNs may be trained on undesirable graph data, which can degrade their performance and reliability. To enable trained GNNs to efficiently unlearn unwanted data, a desirable solution is retraining-based graph unlearning, which partitions the training graph into subgraphs and trains sub-models on them, allowing fast unlearning through partial retraining. However, the graph partition process causes information loss in the training graph, resulting in the low model utility of sub-GNN models. In this paper, we propose GraphRevoker, a novel graph unlearning framework that better maintains the model utility of unlearnable GNNs. Specifically, we preserve the graph property with graph property-aware sharding and effectively aggregate the sub-GNN models for prediction with graph contrastive sub-model aggregation. We conduct extensive experiments to demonstrate the superiority of our proposed approach.
Paper Structure (25 sections, 18 equations, 3 figures, 6 tables)

This paper contains 25 sections, 18 equations, 3 figures, 6 tables.

Figures (3)

  • Figure 1: An example of graph unlearning in a social network.
  • Figure 2: Illustration of the proposed framework.
  • Figure 3: The unlearning power of our proposed framework. This figure shows the F1-score (%) on Cora and Citeseer of the original model, the model affected by low-quality data, and the model unlearned the low-quality data.