A General Framework for Class Label Specific Mutual Information Feature Selection Method

Information theory-based feature selection (ITFS) methods select a single subset of features for all classes based on the following criteria: 1) minimizing redundancy between the selected features and 2) maximizing classification information of the selected features with the classes. A critical issue with selecting a single subset of features is that they may not represent the feature space in which individual class labels can be separated exclusively. Existing methods fail to provide a way to select the feature space specific to the individual class label. To this end, we propose a novel feature selection method called class-label specific mutual information (CSMI) that selects a specific set of features for each class label. The proposed method maximizes the information shared among the selected features and target class label but minimizes the same with all classes. We also consider the dynamic change of information between selected features and the target class label when a candidate feature is added. Finally, we provide a general framework for the CSMI to make it classifier-independent. We perform experiments on sixteen benchmark data sets using four classifiers and found that the CSMI outperforms five traditional, two state-of-the-art ITFS (multi-class classification), and one multi-label classification methods.