Abstract:

Focused on the traditional methods of feature selection for brain functional connectivity matrix derived from Resting-state functional Magnetic Resonance Imaging (R-fMRI) have feature redundancy, cannot determine the final feature dimension and other problems, a new feature selection algorithm was proposed. The algorithm combined Random Forest (RF) algorithm in statistical method, and applied it in the identification experiment of schizophrenic and normal patients, according to the features are obtained by the classification results of out of bag data. The experimental results show that compared to the traditional Principal Component Analysis (PCA), the proposed algorithm can effectively retain important features to improve recognition accuracy, which have good medical explanation.

Key words: Random Forest (RF), statistical property, Resting-state functional Magnetic Resonance Imaging (R-fMRI), brain functional connectivity matrix

摘要：

针对由静息态功能磁共振成像(R-fMRI)得到的脑功能连接矩阵数据运用传统特征选择方法处理的结果,存在特征冗余,无法确定最终特征维数等问题,提出一种全新的特征选择算法.该算法在随机森林(RF)算法中结合统计特性,根据袋外数据的分类效果得到保留的特征,并将其运用在对精神分裂患者与正常被试者的识别实验中.实验结果表明,与传统的主成分分析(PCA)方法相比,该算法可以有效保留重要特征,提高识别精度,且保留的特征具有很好的医学解释性.

关键词: 随机森林, 统计特性, 静息态功能磁共振成像, 脑功能连接矩阵