Abstract: In order to deal with complex formal context more efficiency，formal context is represented by matrix，so the compute of a formal context can be converted from a symbolic one to a numerical one，this paper proposes attribute purified context，and it is the way to judge whether a formal context is a purified one.Dually，it can define object purified formal context and purified formal context.For a purified formal context，its embodied association rules and its supplement formal context’s embodied association rules are mutually inverse.And this law will help mining association rule from a complex formal context.

Key words: attribute purified formal context, purified formal context, supplement formal context, association rule

摘要： 为提高处理复杂形式背景的效率，将形式背景用矩阵表示，从而将形式背景上的符号运算转化为矩阵数值运算，提出了属性纯化形式背景，并应用矩阵的数值运算判定属性特征，从而判定一个形式背景是否是属性纯化的。对偶地，可以得到对象纯化形式背景的判定方法。一个形式背景既是属性纯化的又是对象纯化的，则这个形式背景是纯化的。一个纯化的形式背景，其蕴涵的关联规则与其补形式背景上的关联规则互逆，有利于复杂形式背景的关联规则提取。

关键词: 属性纯化形式背景, 纯化形式背景, 补形式背景, 关联规则