Unverified50% confidenceCautionExact time
在特征标准化、归一化或PCA降维时使用整个数据集（包括测试集）的统计量而非仅用训练集，会造成特征构造泄露
1
Sources
50%
Confidence
Long-term
Relevance
8/12/2026
First Seen
Sources
金融机器学习模型为何难以评估？核心挑战与避坑指南
Related Claims
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