Heterogeneous graph neural networks (HGNNs) have powerful capability to embed
rich structural and semantic information of a heterogeneous graph into node
representations. Existing HGNNs inherit many mechanisms from graph neural
networks (GNNs) over homogeneous graphs, especially the attention mechanism and
the multi-layer structure. These mechanisms bring excessive complexity, but
seldom work studies whether they are really effective on heterogeneous graphs.
This paper conducts an in-depth and detailed study of these mechanisms and
proposes Simple and Efficient Heterogeneous Graph Neural Network (SeHGNN). To
easily capture structural information, SeHGNN pre-computes the neighbor
aggregation using a light-weight mean aggregator, which reduces complexity by
removing overused neighbor attention and avoiding repeated neighbor aggregation
in every training epoch. To better utilize semantic information, SeHGNN adopts
the single-layer structure with long metapaths to extend the receptive field,
as well as a transformer-based semantic fusion module to fuse features from
different metapaths. As a result, SeHGNN exhibits the characteristics of simple
network structure, high prediction accuracy, and fast training speed. Extensive
experiments on five real-world heterogeneous graphs demonstrate the superiority
of SeHGNN over the state-of-the-arts on both accuracy and training speed.

本论文通过对异构图神经网络（HGNN）中注意力机制、多层结构进行深入研究，提出了 Simple and Efficient Heterogeneous Graph Neural Network（SeHGNN），该方法采用轻量级平均聚合器预先计算邻居聚合以捕获结构信息，采用长元路径和 Transformer 语义融合模块来更好地利用语义信息，结果表明 SeHGNN 具有简单的网络结构、高预测准确性和快速的训练速度。