title: Unbiased feature selection in learning random forests for high-dimensional data.
abstract: Random forests (RFs) have been widely used as a powerful classification method. However, with the randomization in both bagging samples and feature selection, the trees in the forest tend to select uninformative features for node splitting. This makes RFs have poor accuracy when working with high-dimensional data. Besides that, RFs have bias in the feature selection process where multivalued features are favored. Aiming at debiasing feature selection in RFs, we propose a new RF algorithm, called xRF, to select good features in learning RFs for high-dimensional data. We first remove the uninformative features using p-value assessment, and the subset of unbiased features is then selected based on some statistical measures. This feature subset is then partitioned into two subsets. A feature weighting sampling technique is used to sample features from these two subsets for building trees. This approach enables one to generate more accurate trees, while allowing one to reduce dimensionality and the amount of data needed for learning RFs. An extensive set of experiments has been conducted on 47 high-dimensional real-world datasets including image datasets. The experimental results have shown that RFs with the proposed approach outperformed the existing random forests in increasing the accuracy and the AUC measures.
authors: Shenzhen Key Laboratory of High Performance Data Mining, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China ; University of Chinese Academy of Sciences, Beijing 100049, China ; School of Computer Science and Engineering, Water Resources University, Hanoi 10000, Vietnam.
authors: Thanh-Tung
authors: TT
authors: Nguyen
authors: Shenzhen Key Laboratory of High Performance Data Mining, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China ; College of Computer Science and Software Engineering, Shenzhen University, Shenzhen 518060, China.
authors: Joshua Zhexue
authors: JZ
authors: Huang
authors: Faculty of Information Technology, Vietnam National University of Agriculture, Hanoi 10000, Vietnam.
authors: Thuy Thi
authors: TT
authors: Nguyen