Dear hyena, Actually, looking at this a bit more closely, the first models dedicate 6 parameters to the correlational and variational structure of the three variables that you mention -- 3 variances and 3 covariances; the second model also dedicates 6 parameters -- 3 factor loadings and 3 error variances (with the variance of the factor fixed as a normalization). You don't show the remaining structure of the models, but a good guess is that they are observationally indistinguishable.
John > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf Of hyena > Sent: March-14-09 5:07 PM > To: r-h...@stat.math.ethz.ch > Subject: [R] SEM model testing with identical goodness of fits > > HI, > > I am testing several models about three latent constructs that > measure risk attitudes. > Two models with different structure obtained identical of fit measures > from chisqure to BIC. > Model1 assumes three factors are correlated with each other and model > two assumes a higher order factor exist and three factors related to > this higher factor instead of to each other. > > Model1: > model.one <- specify.model() > tr<->tp,e.trtp,NA > tp<->weber,e.tpweber,NA > weber<->tr,e.webertr,NA > weber<->weber, e.weber,NA > tp<->tp,e.tp,NA > tr <->tr,e.trv,NA > .... > > Model two > model.two <- specify.model() > rsk->tp,e.rsktp,NA > rsk->tr,e.rsktr,NA > rsk->weber,e.rskweber,NA > rsk<->rsk, NA,1 > weber<->weber, e.weber,NA > tp<->tp,e.tp,NA > tr <->tr,e.trv,NA > .... > > the summary of both sem model gives identical fit indices, using same > data set. > > is there some thing wrong with this mode specification? > > Thanks > > ______________________________________________ > 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.
