With the development of graph convolutional networks (GCN), deep learning
methods have started to be used on graph data. In additional to convolutional
layers, pooling layers are another important components of deep learning.
However, no effective pooling methods have been developed for graphs currently.
In this work, we propose the graph pooling (gPool) layer, which employs a
trainable projection vector to measure the importance of nodes in graphs. By
selecting the k-most important nodes to form the new graph, gPool achieves the
same objective as regular max pooling layers operating on images. Another
limitation of GCN when used on graph-based text representation tasks is that,
GCNs do not consider the order information of nodes in graph. To address this
limitation, we propose the hybrid convolutional (hConv) layer that combines GCN
and regular convolutional operations. The hConv layer is capable of increasing
receptive fields quickly and computing features automatically. Based on the
proposed gPool and hConv layers, we develop new deep networks for text
categorization tasks. Our results show that the networks based on gPool and
hConv layers achieves new state-of-the-art performance as compared to baseline
methods.

提出了使用可训练投影向量评估节点重要性来选择新图形的最重要的 K 个节点以达到与图像最大池化层相同目的的图形池 (pooling) 层。同时，结合 GCN 和普通卷积运算进行的混合卷积层 (hConv) 能够快速增加接受野 (receptive field)，自动计算特征等功能，基于提出的 gPool 和 hConv 层，我们为文本分类任务开发了新的深度网络，结果证明基于这些层的网络相比于基线方法具有新的最先进性能。