Sure, something like that. Store each model as an element of a list,
and then use something like
for(i in 1:4){
indices<-combn(1:4, i)
for (j in 1:length(indices[1,])){
new.model<-combine.models(model.pieces[ indices[,j] ] )
#code for analysis....
}
}
Or, if this doesn't fit your problem exactly, some similar approach.
On Apr 9, 2009, at 4:23 PM, Iuri Gavronski wrote:
Jarret,
I've donwloaded the zip file and installed, but maybe have lost some
pre-req check. I have manually installed sna.
Anyway, which would be the approach you suggest? Making (using my
example) 4 different models, one for each construct, then use
combine.models and add.to.models to create the 12 models to be
compared?
Best,
Iuri.
On Thu, Apr 9, 2009 at 8:13 PM, Jarrett Byrnes <byr...@msi.ucsb.edu>
wrote:
install.packages("sem-additions",repos="http://R-Forge.R-
project.org")
Sorry, it's sem-additions on r-forge. Not sem.additions, which is
what I
had originally called it. But they won't take . in the name of a
package.
On Apr 9, 2009, at 4:07 PM, Iuri Gavronski wrote:
Jarret,
Look:
install.packages("sem.additions", repos="http://R-Forge.R-project.org
")
Warning message:
package ‘sem.additions’ is not available
Best,
Iuri.
On Thu, Apr 9, 2009 at 3:10 PM, Jarrett Byrnes <byr...@msi.ucsb.edu>
wrote:
Ivan,
I recently put together the sem.additions package over at R forge
in part
for just such a multiple model problem. THere are a variety of
methods
that
make it easy to add/delete links that could be automated with a
for loop
and
something from the combn package, I think.
http://r-forge.r-project.org/projects/sem-additions/
-Jarrett
On Apr 9, 2009, at 6:39 AM, Iuri Gavronski wrote:
Hi,
I am not sure if R-help is the right forum for my question. If
not,
please let me know.
I have to do some discriminant validity tests with some
constructs. I
am using the method of doing a CFA constraining the correlation
of a
pair of the constructs to 1 and comparing the chi-square of this
constrained model to the unconstrained model. If the chi-square
difference is not significant, then I cannot reject the null
hypothesis that the two constructs are equal.
Well, if you are going to test, say, 4 constructs (A, B, C, and
D),
you will have to have 2*C(4,2) = 12 models to test, 5
constructs, 20
models, and so forth. A tedious and error prone process...
So far, I have been using AMOS for that shake, given that 1) my
university has the license, 2) my other colleagues use it, and
3) I
know it ;)
I would like to know if any of you use R, namely the sem
package, for
that application and if you can share your thoughts/experiences on
using it. I don't thing I would have problems "porting" my
models to
R/sem, but I would like to know if there is an optimized process
of
doing that tests, without manually coding all the dozens of
models.
Best,
Iuri.
______________________________________________
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.
______________________________________________
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.
______________________________________________
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.
______________________________________________
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.
