Linked text representation is critical for many intelligent web applications, such as online advertisement and recommender systems. Recent breakthroughs on pretrained language models and graph neural networks facilitate the development of corresponding techniques. However, the existing works mainly rely on cascaded model structures: the texts are independently encoded by language models at first, and the textual embeddings are further aggregated by graph neural networks. We argue that the neighbourhood information is insufficiently utilized within the above process, which restricts the representation quality. In this work, we propose GraphFormers, where graph neural networks are nested alongside each transformer layer of the language models. On top of the above architecture, the linked texts will iteratively extract neighbourhood information for the enhancement of their own semantics. Such an iterative workflow gives rise to more effective utilization of neighbourhood information, which contributes to the representation quality. We further introduce an adaptation called unidirectional GraphFormers, which is much more efficient and comparably effective; and we leverage a pretraining strategy called the neighbourhood-aware masked language modeling to enhance the training effect. We perform extensive experiment studies with three large-scale linked text datasets, whose results verify the effectiveness of our proposed methods.

本文提出了一种基于文本图的表示学习方法GraphFormers，该方法将语言模型的Transformer块与图神经网络嵌套在一起，将文本编码和图聚合融合到迭代的工作流程中，从全局视角准确地理解每个节点的语义。通过在三个大规模基准数据集上的广泛评估，GraphFormers比SOTA基准模型具有相当的运行效率。

GraphFormers: 融合GNN和Transformer的文本图卷积神经网络表示学习