Structure-Aware Prototypical Neural Process for Few-Shot Graph Classification

作者：Xixun Lin, Zhao Li, Peng Zhang, Luchen Liu, Chuan Zhou, Bin Wang, Zhihong Tian · 发表于：IEEE Transactions on Neural Networks and Learning Systems · 年份：2022 · DOI：10.1109/tnnls.2022.3173318 · 被引用次数：24 · 研究领域：Advanced Graph Neural Networks、Machine Learning in Materials Science、Machine Learning and ELM

Graph classification plays an important role in a wide range of applications from biological prediction to social analysis. Traditional graph classification models built on graph kernels are hampered by the challenge of poor generalization as they are heavily dependent on the dedicated design of handcrafted features. Recently, graph neural networks (GNNs) become a new class of tools for analyzing graph data and have achieved promising performance. However, it is necessary to collect a large number of labeled graph data for training an accurate GNN, which is often unaffordable in real-world applications. Therefore, it is an open question to build GNNs under the condition of few-shot learning where only a few labeled graphs are available. In this article, we introduce a new Structure-aware Prototypical Neural Process (SPNP for short) for a few-shot graph classification. Specifically, at the encoding stage, SPNP first employs GNNs to capture graph structure information. Then, SPNP incorporates such structural priors into the latent path and the deterministic path for representing stochastic processes. At the decoding stage, SPNP uses a new prototypical decoder to define a metric space where unseen graphs can be predicted effectively. The proposed decoder, which contains a self-attention mechanism to learn the intraclass dependence between graphs, can enhance the class-level representations, especially for new classes. Furthermore, benefited from such a flexible encoding-decoding...