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My own bias is that lots of these statements
are on a level with "pink for girls and blue
for boys". 

I'm not a statistician either. 

Nick 
[email protected] 

> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of
> [email protected]
> Sent: 10 December 2004 18:05
> To: [email protected]
> Subject: Re: st: RE: Factor analysis and dummy variables.
> 
> 
> Thanks to Nick and Mark for their inputs.
> 
> Mark, the polychoric and polychoricpca are running forever.
> Is there a better way to do this?
> 
> Nick,
> Unfortunatelly, he left for the weekend.
> 
> But basically, in his reasonning, the PCA is reserved for continuous
> variables while the MCA is reserved for dummy variables. In the same
> idea, categorical variables (more than two responses) are to be used
> with PCA.
> 
> He is a statistician, I am not. I know very few of factor 
> analysis. My little
> understanding is that it creates a common factor from a dispersion in
> varlist.
> 
> My problem is that I want to create an asset index.
> 
> factor radio tv frige bike moto car , pcf factor(5)
> score wealthindex
> 
> xtile wealthgroup5 = wealthindex, nq(5)
> 
> The score I obtain after the factor is of poor quality since 
> I do not have a
> homogenous
> distribution (i.e. approx 20%) of wealthgroup5 subgroups. I 
> have the same
> problem with
> or without weights.
> 
> Any clue what is the best solution?
> 
> Many thanks.
> 
> 
> 
>                                                               
>                                                               
>                
>                       "Nick Cox"                              
>                                                               
>                
>                       <[email protected]>           To:    
>    <[email protected]>                           
>                
>                       Sent by:                         cc:    
>                                                               
>                
>                       owner-statalist@hsphsun2.        
> Subject:  st: RE: Factor analysis and dummy variables.        
>                       
>                       harvard.edu                             
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>                       12/10/2004 12:42 PM                     
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>                       Please respond to                       
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>                       statalist                               
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> 
> 
> 
> What did your colleague say was the
> reason for it being "wrong"? What
> are your criteria for recognising
> a "best command"?
> 
> Nick
> [email protected]
> 
> [email protected]
> 
> > I know this question has been asked several times, but it's
> > worth asking again.
> >
> > Is it right to perform PCA analysis with dummy (0/1) variables?
> >
> > I used to code :
> >
> > factor radio tv frige bike moto car , pcf factor(5)
> >
> > where radio tv ... are dummy (0/1),
> >
> > but a colleague just told me I am wrong.
> >
> > A MCA in his mind is better.
> >
> > What is the best command in that case? Just to make sure.
> >
> 
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