Abstract: This paper took an improved algorithm based on inter-class separability directed acyclic graph support vector machine (DAG-SVM) for text classification.The method has adjusted the DAG structure according to inter-class distribution and the distance between centers. It has solved the problems of fixed structure and random single node location in traditional DAG-SVM multi-classification method.The experiments show that the algorithm has improved the accuracy.

Key words: text classification, support vector machine, DAG-SVM, inter-class separability