这篇论文讲怎么解决图数据里类别不平衡的问题，NodeImport能动态挑出重要节点，不用重新生成太多假数据，效果还比现有方法好。做图神经网络、节点分类的可以看看方法细节。
论文提出NodeImport框架，针对图神经网络在类不平衡场景下对少数类过拟合的问题。该方法通过构建平衡元集来测量节点重要性，筛选出能提升无偏模型性能的标签、未标签及合成节点。理论推导出直接评估节点重要性的公式，并引入阈值用于节点选择。在多个数据集上使用GCN、GAT等架构进行测试，结果优于现有基线方法。
NodeImport: Imbalanced Node Classification with Node Importance Assessment
In real-world applications, node classification on graphs often faces the challenge of class imbalance, where majority classes dominate training, resulting in biased model performance. Traditional GNNs often struggle in such scenarios, as they tend to overfit to majority classes while underrepresenting minority classes. Existing solutions, which either prioritize nodes based on class size or synthesize new nodes for minority classes, often fall short of effectively addressing this imbalance issue. This paper introduces an approach to class-imbalanced node classification by utilizing a balanced meta-set for importance measurement, where a training node is considered significant if it enhances model performance under an unbiased setting. Our method identifies important nodes that can counteract class imbalance and utilizes them for model training, allowing for fine-grained and dynamic node selection throughout the training process. We theoretically derive a formula to directly assess node importance, reducing computational overhead and providing an intuitive threshold for node selection. Guided by this metric, we develop a novel framework that filters valuable labeled, unlabeled, and synthetic nodes that enhance model performance in an unbiased context. A key advantage of this framework is its separation of the synthetic node generation process from the filtering process, ensuring compatibility with various node generation methods. Furthermore, we introduce a strategy to construct a high-quality meta-set that closely approximates the overall feature distribution, ensuring robust representation of each class. We evaluate our framework, NodeImport, across multiple datasets using popular GNN architectures, demonstrating its superiority over existing baselines. Our results highlight the flexibility and effectiveness of the framework in mitigating class imbalance, leading to improved outcomes.