similar to: SEM multigroup modeling

Hello All, I have a question about measurement invariance in a multigroup SEM. I am of the impression that one cannot test the equality of structural paths across groups without demonstrating measurement invariance of latent factors first. At a minimum, this would involve demonstrating that corresponding factor loadings do not differ across groups using, say, a difference in chi-square test. Am

Hi list members, I saw a couple lavaan posts here so I think I?m sending this to the correct list. I am trying to run a multigroup analysis with lavaan in order to compare behavioural correlations across two populations. I?m following the method suggested in the paper by Dingemanse et al. (2010) in Behavioural Ecology. In one of the groups, lavaan returns negative variance for one path and I?m

As the attachement,I wanna draw multi group plot. But I can only use : plot(x,y...) points(...) It's a heavy work to use these command if there're too many groups to be drawn because I have to use point(....) for many times. I wanna know wheter there's command which can draw the multigroup plot directly? Thanks My best.

Dear R users, Version 2.1-1 of the sem package, for structural equation modeling, is now on CRAN. Unlike version 2.0-0, which was a major overhaul of the package, version 2.1-1 just sprinkles some syntactic sugar on it, introducing the specifyEquations() and cfa() functions; specifyEquations() supports model specification in equation (rather than path) format, and cfa() facilitates compact

Dear R users, Version 2.1-1 of the sem package, for structural equation modeling, is now on CRAN. Unlike version 2.0-0, which was a major overhaul of the package, version 2.1-1 just sprinkles some syntactic sugar on it, introducing the specifyEquations() and cfa() functions; specifyEquations() supports model specification in equation (rather than path) format, and cfa() facilitates compact

Hi everyone, I am trying to change some of the default colors in a multipanel-multigroup lattice graphic, but when I change the panel color to white, the only group that is plotted is the last one, as panel.fill overwrites all the previous ones. Is there any way to set the panel background color for the first panel to a color and keep the rest transparent? My code looks like this: #first set

Hi all, I've got the following matrix : ? mat <- matrix(rnorm(700), ncol=5, dimnames=list( paste("f", c(1:140), sep="_"), c("A", "B", "C", "D", "E"))) I can see that currently most of the multivariate Hotelling T2 tests are limited for application on two groups/samples. I wud appreciate if someone can provide me a

Hello all, This is a general stats question--I realize it is an R help list, so tell me to go away if it is inappropriate. I have a 2 X 2 design, and I have specified four identical path models (one for each level of each factor). I want to test for an interaction at each path--essentially (A1 - A2) - (B1 - B2) != 0. I was thinking of computing a contrast for each path of interest, such that

In efforts to improve optimization tools for R, one of my interests has been getting automatic differentiation capabilities so that analytic rather than numerical derivatives can be used. They would be helpful in several other areas besides optimization, My timings show factors of the order of 1000s in time improvements by avoiding numerical derivatives in some cases. There has been some work in

Hello I am using sem to look at the direct effect of one variable on another but i am uncertain if i am progressing correctly. An example: covar1<-? matrix(c(0.4,-0.2,3,-0.2 , 0.3,-2 , 3 ,-2 , 60), nrow=3,byrow=T) rownames(covar1)<-colnames(covar1)<-c("endo","exo","med") path1<-matrix(c(? ? "exo -> endo",? "g1", NA,

Hello all, I have an issue where I am generating data and trying to confirm the estimates using a sem. I keep getting an error about the degree of freedom being negative "Error in sem.default(ram, S = S, N = N, raw = raw, data = data, pattern.number = pattern.number, : The model has negative degrees of freedom = -6" Can someone explain this error or tell me what is wrong with my

Hello, I have conducted an SEM in which the resultant standardized path coefficients are much higher than would be expected from the raw correlation matrix. To explore further, I stripped the model down to a simple bivariate relationship between two variables (NDVI, and species richness), where it's my understanding that the SEM's standardized path coefficient should equal the correlation

Hello All, Recently, I was asked to help out with an SEM cross-validation analysis. Initially, the project was based on "sample-splitting" where half of cases were randomly assigned to a training sample and half to a testing sample. Attempts to replicate a model developed in the training sample using the testing sample were not entirely successful. A number of parameter estimates were

Can somebody takes part in adding the following functionality to Samba4: It is necassary to do Samba4 computer as multi DMB or I think more likely as multi LMB for multigroups additionally to default main domain / group. That is necasary to add to Samba4 such functionality in Samba4 code and add to smb.conf at least 3 parameters: - multi browser support = yes/no - switch on / off this feature -