Re: [R] Factor loadings and principal component plots

About this list Date view Thread view Subject view Author view Attachment view

From: Jari Oksanen (jarioksa@sun3.oulu.fi)
Date: Tue 04 May 2004 - 16:43:03 EST


Message-id: <1083652983.7580.2.camel@biol102145.oulu.fi>

On Tue, 2004-05-04 at 09:34, Prof Brian Ripley wrote:

>
> Yes, but princomp is the recommended way, not prcomp.

But the documentation seems to recommend prcomp:

?prcomp:

 
     The calculation is done by a singular value decomposition of the
     (centered and scaled) data matrix, not by using 'eigen' on the
     covariance matrix. This is generally the preferred method for
     numerical accuracy.

?princomp:

     The calculation is done using 'eigen' on the correlation or
     covariance matrix, as determined by 'cor'. This is done for
     compatibility with the S-PLUS result. A preferred method of
     calculation is to use 'svd' on 'x', as is done in 'prcomp'.

Just confused, jari oksanen

-- 
Jari Oksanen <jarioksa@sun3.oulu.fi>

______________________________________________ R-help@stat.math.ethz.ch mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html


About this list Date view Thread view Subject view Author view Attachment view

This archive was generated by hypermail 2.1.3 : Mon 31 May 2004 - 23:05:07 EST