关键词: 决策树, 客户流失, 熵函数

Abstract: This article analyzes the ID3 decision tree algorithm which is widely used in classifying and forecasting，and points out some defections of this algorithm such as value deviation and operation inefficient and so on.On base of the analysis of ID3，an improved ID3 algorithm is presented to apply it to forecaste the customer’s churn in a communication company.The improved algorithm overcomes the value deviation through the attribute weighting，obviously improves the operation efficiency using the entropy function’s recursion and by looking up the table of dual entropy functions.The application result indicates that the improved algorithm obviously enhances the performance.

Key words: decision tree, customer’s churn, entropy function