QC-SMOTE通过质量控制生成更可靠的合成样本,提升不平衡分类效果。
QC-SMOTE: Quality-Controlled SMOTE for Imbalanced Classification

- 用邻域可信度评分筛选可靠少数类样本,指导合成策略。
- 在30个数据集上平均AUC-ROC和宏F1均优于现有方法,尤其在严重不平衡时表现突出。
- 适合处理噪声大、类别重叠的不平衡数据,对算法鲁棒性要求高的场景适用。
类别不平衡在分类任务中构成重大挑战,现有方法如SMOTE常在噪声区域或类别重叠区生成低质量合成样本。本文提出QC-SMOTE,一种质量可控的过采样框架,通过结合局部密度、安全阈值及远离多数类的程度,计算少数类样本的综合邻域可信度。合成候选样本采用基于IPQ的K选最优策略,评估中点纯度,并在必要时进行多数类清除,生成过程由样本可信度与边界信息量引导。生成行为随重叠-不平衡程度自适应调整插值范围与选择标准,匹配局部数据几何结构。当邻域纯度低于自适应阈值时,低质量合成样本将被原始少数类样本复制替代,实现严重噪声区域的渐进退化。在30个不平衡数据集上采用重复分层交叉验证实验表明,QC-SMOTE在所有对比方法中取得最强平均AUC-ROC与宏F1,在中等至严重不平衡条件下增益尤为明显。结果证明,质量感知且几何自适应的合成采样对鲁棒不平衡分类至关重要。
原文摘要 · Abstract (English)
Class imbalance poses a significant challenge in classification, where existing methods such as SMOTE often generate low-quality synthetic samples in regions with noise or class overlap. We propose QC-SMOTE, a quality-controlled oversampling framework that estimates minority sample reliability using a composite neighbourhood trustworthiness score combining local density, safe-level, and isolation from the majority class. Synthetic candidates are generated using an IPQ-guided best-of-K strategy that evaluates midpoint purity and, when required, majority clearance, with allocation guided by sample reliability and boundary informativeness. Generation behaviour adapts across overlap--imbalance regimes, adjusting interpolation range and selection criteria to match local data geometry. Low-quality synthetic samples are replaced with original minority duplicates when neighbourhood purity falls below an adaptive threshold, providing graceful degradation by reverting to duplication in severely noisy regions. Experiments on 30 imbalanced datasets using repeated stratified cross-validation show that QC-SMOTE achieves the strongest average AUC-ROC and Macro F1 among the compared oversampling methods, with particularly clear gains under moderate and severe imbalance. These results demonstrate the importance of quality-aware, geometry-adaptive synthetic sampling for robust imbalanced classification.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。