Principle component analysis

phthao05 <phthao05 <at> gmail.com> writes:

  [snip]

Because I have just learn R language in a few day so I have many problem. 
1) I don't know why PCA rotation function not run although I try many times.
Would you please hepl me and explain how to read the PCA map (both of
rotated and unrotated) in a concrete example. 
2) Where I can find document relate: Plan S(A), S(A*B), S(A)*B?
       Thanks alot.

You haven't given us enough information to help you: please
read the posting guide (referenced in every R-help posting).

(1) you need to give _us_ a "concrete example" (not the other
way around) that shows us what you tried, how far you got,
and what "not run" means (see the posting guide for more information
about asking questions on the list).

(2) Can you clarify the question?  I don't know what "Plan S(A),
S(A*B), S(A)*B" means, at all ...

  Venables and Ripley's book is a terse, but useful, introduction
to many topics in R.  There are other books listed on the web
page ...

  (and by the way, that's "principal" component analysis --
I wish I could ignore it but I can't)

  good luck,
    Ben Bolker

 1) I don't know why PCA rotation function not run although I try many times.
 Would you please hepl me and explain how to read the PCA map (both of
 rotated and unrotated) in a concrete example.

If you used the example from here [1], there's a typo in the document.
It should look like the following:

library(psych)
fit <- factor.pa(mydata, nfactors=3, rotate="varimax") # rotatE; not rotatION
fit # print results

Also, there are a _lot_ of rotation methods in GPArotation. Load the
package and use in the function above, say, rotate="quartimax". For
un-rotated PCA, I'd imagine it would be rotate="none".

Liviu

[1] http://www.statmethods.net/advstats/factor.html