[R] CFA in R/sem package

[Iuri Gavronski]

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 <byrnes at 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 <byrnes at 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 at 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 at 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 at 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.
>