CuGNN: Cross-perspective contrastive learning for enhancing unsupervised GNNs beyond homophily
摘要
Heterophily in graph neural networks has received significant attention due to its ability to adapt to challenging graph-structured data. Most existing research focuses on supervised learning strategies, leveraging edge heterophily as a supervisory signal to guide message passing. However, these strategies are challenging to apply in more common unsupervised scenarios, where representing heterophilic graphs becomes even more difficult. Specifically, two challenges arise: capturing edge heterophily in graph-structured data under unsupervised conditions, and utilizing this information for effective representation learning. To address the first challenge, we introduce a new strategy called the Feature-Distribution Embedding based Edge-Heterophily Identification, which identifies edge heterophily by evaluating the similarity between feature-distribution embedding. Additionally, we propose an effective adaptive mechanism to enhance the capture of edge heterophily information. For the second challenge, we propose a latent-space cross-perspective contrastive strategy that improves the unsupervised optimization of the heterophily graph neural network, further refining the edge-heterophily identifications. To integrate these strategies, we propose a novel framework: