[R] PCA loadings differ vastly!

[gregor rolshausen]

hi, I have two questions:

#first (SPSS vs. R):

I just compared the output of different PCA routines in R (pca, prcomp, 
princomp) with results from SPSS. the loadings of the variables differ 
vastly! in SPSS the variables load constantly higher than in R.
I made sure that both progr. use the correlation matrix as basis. I 
found the same problem with rotated values (varimax rotation and rtex=T 
rotation).

can anyone comment ?

second:

princomp(data, cor=T, rtex=T)$loadings  vs.  princomp(data, cor=T, 
rtex=F)$loadings

gives me different loadings (expected because of rotation) with one 
dataset (11 variables)
but returns the SAME values with another dataset (3 variables).

comments ??

thanks for your time!

cheers,
gregor