[R] factor analysis

[Pierre BADY]

hi all,

In the library 'ade4’, there are two eigenanalysis which enable the ordination 
of the categorical variables. 

1- Multiple Correspondence Analysis (MCA, Tenenhaus & Young 1985) performs the 
multiple correspondence analysis of a factor table (see the 
function 'dudi.acm’). 

2- the "mixed factorial analysis" (Hill & Smith 1976)  enables the ordination 
of tables mixing quantitative variables and factors (functions 'dudi.mix’ 
or  'dudi.hillsmith’).


I hope this helps,

P.BADY



En réponse à John Fox <jfox at mcmaster.ca>:
> Dear Allan,
> 
> I assume that the categorical data are ordinal. There are methods for
> factor analyzing ordinal data (e.g., using polychoric correlations)
> and
> mixed ordinal and interval data, but as far as I know, these aren't
> implemented in R.
> 
> John
> 
> On Thu, 13 May 2004 18:32:11 +0200
>  allan clark <allan at stats.uct.ac.za> wrote:
> > hi all
> > 
> > this is a stats question.
> > 
> > when undertaking factor analysis should the variables included
> always
> > be
> > continiuos random variables? could one include categorical data? e.g
> > some survey type data
> > 
> > my gut feeling is that one should not include categorical type data
> > since factor analysis is based on the eigenanalysis of the
> > correlation
> > matrix of a group of variables. The introduction of categorical data
> > into a data set might "mess up" the corelation matrix.
> > 
> > ______________________________________________
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> > https://www.stat.math.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide!
> > http://www.R-project.org/posting-guide.html
> 
> 
> --------------------------------
> John Fox
> Department of Sociology
> McMaster University
> Hamilton, Ontario, Canada
> http://socserv.mcmaster.ca/jfox/
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html
> 
> 



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