Graph Neural Networks (GNNs) achieve state-of-the-art performance in various graph-related tasks. However, the black-box nature often limits their interpretability and trustworthiness. Numerous explainability methods have been proposed to uncover the decision-making logic of GNNs, by generating underlying explanatory substructures. In this paper, we conduct a comprehensive review of the existing explanation methods for GNNs from the perspective of graph generation. Specifically, we propose a unified optimization objective for generative explanation methods, comprising two sub-objectives: Attribution and Information constraints. We further demonstrate their specific manifestations in various generative model architectures and different explanation scenarios. With the unified objective of the explanation problem, we reveal the shared characteristics and distinctions among current methods, laying the foundation for future methodological advancements. Empirical results demonstrate the advantages and limitations of different explainability approaches in terms of explanation performance, efficiency, and generalizability.

结合图生成的角度，本文综述了用于图神经网络的解释方法，并就生成解释方法提出了统一的优化目标，包括归因和信息约束两个子目标。通过揭示现有方法的共享特性和差异，为未来的方法改进奠定了基础。实证结果对不同的解释方法在解释性能、效率和泛化能力方面的优势和局限性进行了验证。

图神经网络的生成式解释：方法与评估