On Tue, 14 Sep 2004, Francisco Chamu wrote: > I have run this on both Windows 2000 and XP. All I did was install > the binaries from CRAN so I think I am using the standard Rblas.dll. > > To reproduce what I see you must run the code at the beginning of the > R session.
We did, as you said `start a clean session'. I think to reproduce what you see we have to be using your account on your computer. > After the second run, all subsequent runs give the same > result as the second set. > > Thanks, > Francisco > > > On Tue, 14 Sep 2004 08:29:25 +0200, Uwe Ligges > <[EMAIL PROTECTED]> wrote: > > Prof Brian Ripley wrote: > > > I get the second set each time, on Windows, using the build from CRAN. > > > Which BLAS are you using? > > > > > > Works also well for me with a self compiled R-1.9.1 (both with standard > > Rblas as well as with the Rblas.dll for Athlon CPU from CRAN). > > Is this a NT-based version of Windows (NT, 2k, XP)? > > > > Uwe > > > > > > > > > > > On Tue, 14 Sep 2004, Francisco Chamu wrote: > > > > > > > > >>I start a clean session of R 1.9.1 on Windows and I run the following code: > > >> > > >> > > >>>library(MASS) > > >>>data(painters) > > >>>pca.painters <- princomp(painters[ ,1:4]) > > >>>loadings(pca.painters) > > >> > > >>Loadings: > > >> Comp.1 Comp.2 Comp.3 Comp.4 > > >>Composition 0.484 -0.376 0.784 -0.101 > > >>Drawing 0.424 0.187 -0.280 -0.841 > > >>Colour -0.381 -0.845 -0.211 -0.310 > > >>Expression 0.664 -0.330 -0.513 0.432 > > >> > > >> Comp.1 Comp.2 Comp.3 Comp.4 > > >>SS loadings 1.00 1.00 1.00 1.00 > > >>Proportion Var 0.25 0.25 0.25 0.25 > > >>Cumulative Var 0.25 0.50 0.75 1.00 > > >> > > >>However, if I rerun the same analysis, the loadings of the first > > >>component have the opposite sign (see below), why is that? I have > > >>read the note > > >>in the princomp help that says > > >> > > >> "The signs of the columns of the loadings and scores are arbitrary, > > >> and so may differ between different programs for PCA, and even > > >> between different builds of R." > > >> > > >>However, I still would expect the same signs for two runs in the same session. > > >> > > >> > > >>>pca.painters <- princomp(painters[ ,1:4]) > > >>>loadings(pca.painters) > > >> > > >>Loadings: > > >> Comp.1 Comp.2 Comp.3 Comp.4 > > >>Composition -0.484 -0.376 0.784 -0.101 > > >>Drawing -0.424 0.187 -0.280 -0.841 > > >>Colour 0.381 -0.845 -0.211 -0.310 > > >>Expression -0.664 -0.330 -0.513 0.432 > > >> > > >> Comp.1 Comp.2 Comp.3 Comp.4 > > >>SS loadings 1.00 1.00 1.00 1.00 > > >>Proportion Var 0.25 0.25 0.25 0.25 > > >>Cumulative Var 0.25 0.50 0.75 1.00 > > >> > > >>>R.version > > >> > > >> _ > > >>platform i386-pc-mingw32 > > >>arch i386 > > >>os mingw32 > > >>system i386, mingw32 > > >>status > > >>major 1 > > >>minor 9.1 > > >>year 2004 > > >>month 06 > > >>day 21 > > >>language R > > >> > > >>BTW, I have tried the same in R 1.9.1 on Debian and I can't reproduce > > >>what I see > > >>on Windows. In fact all the runs give the same as the second run on Windows. > > >> > > >>-Francisco > > >> > > >>______________________________________________ > > >>[EMAIL PROTECTED] mailing list > > >>https://stat.ethz.ch/mailman/listinfo/r-help > > >>PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > > >> > > >> > > > > > > > > > > > > -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
