此分类算法首先计算未知类别样本的重构系数，定义一种误差作为判别标准，根据此误差的大小判断样本的类别归属。

This algorithm firstly computes the reconstruction weights of unknown samples. Then an error, on which the class of samples can be decided based, is defined as a criterion.

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文本分类是数据挖掘领域中重要分支之一，其任务是对未知类别的文本进行自动处理，判断它们所属的预定义类别集合中的类别。

Text classification is an important branch in data mining filed, which is responsible for automatically dealing with those class-unknown texts and judging which pre-defined class sets they reside in.

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例如，类别为“未知”的数据通常表明一个列只有null值或者为空，可能不被使用。

For example, data classified as "unknown" usually indicates a column that is null or empty and probably not used.

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