[R] How to do a PCA with ordered variables?

Stas Kolenikov skolenik at gmail.com
Thu Sep 17 19:52:39 CEST 2009


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_difford at 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?
>>
>
> --
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> Sent from the R help mailing list archive at Nabble.com.
>
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>



-- 
Stas Kolenikov, also found at http://stas.kolenikov.name
Small print: I use this email account for mailing lists only.




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