由于它是范围谓词，而且没有频度和直方图统计数据可用，过滤因子是用基础统计信息HIGH2KEY和LOW2KEY计算得出的。

Since it is a range predicate and there are no frequency and histogram statistics available, the filter factor is calculated with the basic statistics information HIGH2KEY and LOW2KEY.

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提取直方图特征函数(HCF)域21维统计矩特征组成特征向量，用支持向量机(SVM)训练分类器。

Extract 21-dimensional statistical characteristics of histogram characteristic function (HCF) field, training classifier with the support vector machine (SVM).

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