Michael Baum posted on Saturday, December 20, 2008 - 9:16 pm
I'm looking for a worked example of EFA for longitudinal twin data (multiple ordinal indicators). I have failed to locate such an example (likely a result of my relative inexperience with the website/software) and was hoping you could point me in the right direction.
The MODEL commands for multiple indicator growth for CFA for categorical outcomes are shown in the user's guide on pages 546-547. Multiple indicator growth is also described in short course Topic 4 beginning with Slide 77. For EFA, you can use the new MODEL command language described in the Version 5.1 Examples and Language Addendums which are on the website with the user's guide.
Thank you for point me to these materials. I was able to conduct the EFA. Now when I try to move on to a CFA framework, I get the following error message:
Unknown variable(s) in a BY statement: (1)-
I'm following the example in Topic 4 of your slides and although I have been able to fit a model where loadings vary by time, I would like to follow that with a model where loadings are invariant across time. However, when I attempt to follow the example I get the error message above. (Data consists of three time points, 2 observations per cluster and 7 ordinal/5-point indicators). Below are my analysis and model statements:
ANALYSIS: type = complex ; ESTIMATOR IS WLSMV; rotation = geomin;
MODEL: f1to7_3 BY fq3_1 fq3_2-fq3_7 (1)-(6); f1to7_7 BY fq7_1 fq7_2-fq7_7 (1)-(6); f1to7_14 BY fq14_1 fq14_2-fq14_7 (1)-(6);
! below allows factors to be correlated over time; f1to7_3 with f1to7_7 f1to7_14; f1to7_7 with f1to7_14;