학술논문

Motor Imagery Classification with Covariance Matrices and Non-Negative Matrix Factorization
Document Type
Conference
Source
2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) Engineering in Medicine and Biology Society (EMBC), 2019 41st Annual International Conference of the IEEE. :3083-3086 Jul, 2019
Subject
Bioengineering
Electroencephalography
Covariance matrices
Feature extraction
Matrix decomposition
Indexes
Training
Geometry
BCI
non-negative matrix factorization
motor imagery
channel selection
Riemannian geometry
NCA
Language
ISSN
1558-4615
Abstract
In this paper, we aim at finding the smallest set of EEG channels that can ensure highly accurate classification of motor imagery (MI) dataset and maintain the optimum Kappa score. Non-negative matrix factorization (NMF) is used for important and discriminant EEG channel selection. Further, the theory of Riemannian geometry in the manifold of covariance matrices is used for feature extraction. At last, the neighborhood component feature selection (NCFS) algorithm is used to select the small subset of important features from the given set of features. The significance of the proposed work is two-fold: 1) it greatly reduces the time complexity and the amount of overfitting by reducing the unnecessary EEG channels and redundant features. 2) it increases the classification accuracy of the model by selecting only subject-specific EEG channels. The proposed algorithm is tested on BCI Competition IV,2a dataset to validate the performance. The proposed approach has achieved 77.91% average classification accuracy and 0.626 mean Kappa score.