Re: [R] Questions about results from PCAproj for robust principal component analysis

2007-02-14 Thread Talbot Katz
Professor Filzmoser. Thank you so much for the detailed response. It is very helpful. -- TMK -- 212-460-5430home 917-656-5351cell >From: Peter Filzmoser <[EMAIL PROTECTED]> >To: Talbot Katz <[EMAIL PROTECTED]> >CC: r-help@stat.math.ethz.ch >Subject: Re: Questions about results from P

Re: [R] Questions about results from PCAproj for robust principal component analysis

2007-02-14 Thread Peter Filzmoser
Hi, PCAproj is mainly designed for robust PCA and not for classical PCA. Therefore, when applying classical estimators to the results of a robust PCA, like the mean to the robust PCA scores, this will usually not give zeros. The robust PCs have been centred robustly, and not classically by the mea

[R] Questions about results from PCAproj for robust principal component analysis

2007-02-13 Thread Talbot Katz
Hi. I have been looking at the PCAproj function in package pcaPP (R 2.4.1) for robust principal components, and I'm trying to interpret the results. I started with a data matrix of dimensions RxC (R is the number of rows / observations, C the number of columns / variables). PCAproj returns a