Graph representation learning has emerged as a powerful technique for real-world problems. Various downstream graph learning tasks have benefited from its recent developments, such as node classification, similarity search, graph classification, and link prediction. However, prior arts on graph representation learning focus on domain specific problems and train a dedicated model for each graph, which is usually non-transferable to out-of-domain data. Inspired by recent advances in pre-training from natural language processing and computer vision, we design Graph Contrastive Coding (GCC) -- an unsupervised graph representation learning framework -- to capture the universal network topological properties across multiple networks. We design GCC's pre-training task as subgraph-level instance discrimination in and across networks and leverage contrastive learning to empower the model to learn the intrinsic and transferable structural representations. We conduct extensive experiments on three graph learning tasks and ten graph datasets. The results show that GCC pre-trained on a collection of diverse datasets can achieve competitive or better performance to its task-specific trained-from-scratch counterparts. This suggests that the pre-training and fine-tuning paradigm presents great potential for graph representation learning.

本论文提出了一个自监督的图神经网络预训练框架Graph Contrastive Coding（GCC），通过子图实例区分学习网络的建构，利用对比学习增强图神经网络的内在和可迁移的结构表现，并在十个图数据集上展开实验，结果表明，GCC对于包括节点分类、相似性搜索和图分类等三个图学习任务，展现出与特定任务和从零开始训练的对应模型相竞争的性能，同时显示了预训练和微调范式在图表示学习中有很大的潜力。

GCC: 图形对比编码用于图神经网络预训练