In this paper, we propose a new model to learn Adaptive Kernel-based Representations (AKBR) for graph classification. Unlike state-of-the-art R-convolution graph kernels that are defined by merely counting any pair of isomorphic substructures between graphs and cannot provide an end-to-end learning mechanism for the classifier, the proposed AKBR approach aims to define an end-to-end representation learning model to construct an adaptive kernel matrix for graphs. To this end, we commence by leveraging a novel feature-channel attention mechanism to capture the interdependencies between different substructure invariants of original graphs. The proposed AKBR model can thus effectively identify the structural importance of different substructures, and compute the R-convolution kernel between pairwise graphs associated with the more significant substructures specified by their structural attentions. Since each row of the resulting kernel matrix can be theoretically seen as the embedding vector of a sample graph, the proposed AKBR model is able to directly employ the resulting kernel matrix as the graph feature matrix and input it into the classifier for classification (i.e., the SoftMax layer), naturally providing an end-to-end learning architecture between the kernel computation as well as the classifier. Experimental results show that the proposed AKBR model outperforms existing state-of-the-art graph kernels and deep learning methods on standard graph benchmarks.

提出了一种新的自适应基于核的表示（AKBR）模型，通过引入特征通道注意机制捕捉原始图形的不同子结构不变量之间的相互依赖关系，从而有效地将更重要的子结构的结构关注率指定的成对图形之间的 R 卷积核计算为数据输入 softmax 层的 AKBR 模型。实验结果表明，所提出的 AKBR 模型在标准图形基准测试上优于现有的最先进的图形核和深度学习方法。

AKBR: 图分类的自适应基于核的表示学习