Provides an approximation of traditional PCA described by Park and Klabjan (2016) as a subroutine for awl1pca.
L2PCA_approx(ev.prev, pc.prev, projDim, X.diff)
'L2PCA_approx' returns a list containing the following components:
Estimate of eigenvalues of the covariance matrix.
Estimate of eigenvectors of the covariance matrix.
matrix of principal component loadings from a previous iteration of awl1pca
vector of eigenvalues from previous iteration of awl1pca
number of dimensions to project data into, must be an integer
The difference between the current weighted matrix estimate and the estimate from the previous iteration
The calculation is performed according to equations (11) and (12) in Park and Klabjan (2016). The method is an approximation for traditional principal component analysis.
Park, Y.W. and Klabjan, D. (2016) Iteratively Reweighted Least Squares Algorithms for L1-Norm Principal Component Analysis, IEEE International Conference on Data Mining (ICDM), 2016.
awl1pca