【摘要】 约略集理论是一种能处理数据中不确定和噪音的有效数学工具，是数据挖掘的重要方法．结合数据分类层次，提出了利用约略集理论挖掘多层次规则的方法，挖掘过程包含约减的求解、等价类的构造、差别矩阵的建立、规则的挖掘４个阶段，并举例说明了多层次规则的挖掘过程．更多还原

【Abstract】 Data mining is one of fast growing advanced research fields. Dependency between data is one of the most important aspects of data mining. As an important method of data mining, rough set theory is a powerful mathematical tool to deal with uncertainty and noise. By use of the taxonomies of data, a rough set approach to mining multiple level rules is proposed. The mining procedure consists of 4 paragraphs: finding reduct, constructing equivalent classes, building difference matrix and mining rules. The rules mining process is illustrated by an example.更多还原