If you are really serious about your variables being ordinal, you should analyze them using polychoric correlations. See polycor package by John Fox.
On Thu, Sep 17, 2009 at 10:52 AM, Mark Difford <mark_diff...@yahoo.co.uk> wrote: >>> I have used the dudi.mix method from the ade4 package, but when I do the >>> $index it shows >>> me that R has considered my variables as quantitative. > >>> What should I do? > > You should make sure that they are encoded as ordered factors, which has > nothing to do with ade4's dudi.mix(). > > ## > ?ordered > > Mark. > > > > P.Branco wrote: >> >> Hi, >> >> I want to do a pca using a set of variables which are ordered. I have used >> the dudi.mix method from the ade4 package, but when I do the $index it >> shows me that R has considered my variables as quantitative. >> >> What should I do? >> > > -- > View this message in context: > http://www.nabble.com/How-to-do-a-PCA-with-ordered-variables--tp25491950p25491969.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- Stas Kolenikov, also found at http://stas.kolenikov.name Small print: I use this email account for mailing lists only. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
