[R] SEM with dichotomous indicators

[John Fox]

Dear Renata,

You can do this by combining the sem() and boot.sem() functions in the
sem package with hetcor() in the polycor package; boot.sem() computes
standard errors for parameter estimates by bootstrapping.

See ?boot.sem for an example of a confirmatory factor-analysis model
with ordinal indicators. See ?sem for many examples of
structural-equation models with latent variables. Just combine the two.
Note that a dichotomous indicator is in effect a two-category ordinal
variable and may be handled as such. For example, the polychoric
correlation between two dichtomous variables is just their tetrachoric
correlation.

I hope this helps,
 John 

On Mon, 10 Oct 2005 11:23:25 -0300
 "Renata" <renata at lipe.com.br> wrote:
> Hello,
> 
>  
> 
> I'd like to know if there is a way to fit a Structural equation model
> with
> dichotomous indicators (ex: problem with a phone solved/ or not)
> having
> effects on a ordinal variable.
> 
> How I do that using R?
> 
> Do you have an example with the code in R that you can send to me?
> 
>  
> 
> Thanks a lot! 
> 
> Renata Estrella
> 
> UFRJ, Brasil, Rio de Janeiro
> 
>  
> 
>  
> 
> Renata Leite Estrella
> 
> Assistente de Pesquisa
> 
> (21) 3978-8888 Ramal  8841
> 
> www.lipe.com.br
> 
>  
> 
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.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/