Hi all,
I am currently working on a project on how intelligence moderates school achievement among young adults. My sample consists of 4,084 German twins aged 17 and 23-24, respectively, who have information on both intelligence and GPA from secondary school. However, the twins' GPAs come from various types of secondary schools so to check whether I need to use school type as a moderator in my GxE analyses, I first want to see what happens if I run separate bivariate variance decomposition analyses for the three school types constraining their parameters equal.
In other words, I would like to set up a three-group program running the bivariate variance decomposition analyses for all three school types at once. However, so far I can only run them separately using the umxACE function. Can anyone help me how to set up a three-group program?
All the best,
Emilie