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.