论文标题
标签增强的图形神经网络,用于半监督节点分类
Label-Enhanced Graph Neural Network for Semi-supervised Node Classification
论文作者
论文摘要
图形神经网络(GNN)已被广泛应用于半监督节点分类任务,其中关键点在于如何充分利用有限但有价值的标签信息。大多数经典GNN仅使用已知标签来计算输出处的分类损失。近年来,已经设计了几种方法来另外利用输入的标签。方法的一部分是通过串联或将其与标签的单热编码添加来增强节点特征,而其他方法通过假设相邻的节点倾向于具有相同的标签来优化图形结构。为了全面播放标签的丰富信息,在本文中,我们为GNN提供了一个标签增强的学习框架,该框架首先将每个标签建模为阶级节点的虚拟中心,然后共同学习节点和标签的表示形式。我们的方法不仅可以平滑属于同一类的节点的表示,而且可以将标签语义显式地编码为GNN的学习过程。此外,还提供了训练节点选择技术,以消除潜在的标签泄漏问题并确保模型的概括能力。最后,提出了一种自适应的自我训练策略,以迭代地扩大具有更可靠的伪标签的训练集,并在模型训练过程中区分每个伪标记节点的重要性。对现实世界和合成数据集的实验结果表明,我们的方法不仅可以始终优于最先进的方法,而且还可以有效地平滑阶级节点的表示。
Graph Neural Networks (GNNs) have been widely applied in the semi-supervised node classification task, where a key point lies in how to sufficiently leverage the limited but valuable label information. Most of the classical GNNs solely use the known labels for computing the classification loss at the output. In recent years, several methods have been designed to additionally utilize the labels at the input. One part of the methods augment the node features via concatenating or adding them with the one-hot encodings of labels, while other methods optimize the graph structure by assuming neighboring nodes tend to have the same label. To bring into full play the rich information of labels, in this paper, we present a label-enhanced learning framework for GNNs, which first models each label as a virtual center for intra-class nodes and then jointly learns the representations of both nodes and labels. Our approach could not only smooth the representations of nodes belonging to the same class, but also explicitly encode the label semantics into the learning process of GNNs. Moreover, a training node selection technique is provided to eliminate the potential label leakage issue and guarantee the model generalization ability. Finally, an adaptive self-training strategy is proposed to iteratively enlarge the training set with more reliable pseudo labels and distinguish the importance of each pseudo-labeled node during the model training process. Experimental results on both real-world and synthetic datasets demonstrate our approach can not only consistently outperform the state-of-the-arts, but also effectively smooth the representations of intra-class nodes.