An Improved Minimum Redundancy Maximum Relevance Approach for Feature Selection in Gene Expression Data

In this article, an improved feature selection technique has been proposed. Mutual Information is taken as the basic criterion to find the feature relevance and redundancy. The mutual information between a feature and class labels defines the relevance of that feature. Again, the mutual information among different features defines the correlation i.e., the redundancy among those features. Now our objective is to find such a feature set for which the mutual information among the features and the class labels are maximized and the mutual information among the features are minimized. Therefore, the goal of the proposed method is to find the most relevant and least redundant feature set. The number of output features is provided by the user. First the most relevant feature is added to the empty final feature set. Then in each iteration a non-dominated feature set with respect to relevance and redundancy is generated and from this set of features, the most relevant and non-redundant feature is included in the final feature set. Thereafter, in an incremental way a feature is added in every iteration and this step is repeated while the size of the final feature set is equal to the user given number of features. The features contained by the final feature set have maximum relevance and least correlation. The proposed method is applied on microarray gene expression data to find the most relevant and non-redundant genes and the performance of the proposed method is compared with that of the popular mRMR (MIQ) and mRMR (MID) schemes on several real-life data sets.