I want to run a simulation using
simsem to determine the sample size to use in a study using path analysis. The conceptual model for my study is as below, with 2 independent variables, 1 mediator and 2 moderators.
I am following the reference book suggested in this answer for how to run the simulation (Latent Variable Modeling Using R: A Step-by-Step Guide by A. Alexander Beaujean). I would like to estimate the error variance of M and Y to use in the simulation. However, the book only provides a method for estimating error variance for a simple regression (i.e, 1-R^2, using path tracing rules). How can I calculate error variances in my case?