I am wanting to use the Monte Carlo simulation study to create longitudinal data (two time points). Is there anyway in which I can create the two time points separately but in the same program? Also is there a way in which I can create the second time point but indicate that the distribution is conditional on the first time point? I have tried to create the data all together and indicate that the variables are correlated across time but I have been running into some problems mostly with the covariance matrix not being positive definite. I think my problem can be solved if I create each time point separately.
The data should be generated together. You should solve the problems you ran into trying to generate the two time points together. Send the output that shows the problems and your license number to firstname.lastname@example.org.