Hello!

I'm having trouble running SEM on longitudinal data (4 waves - (same group followed over time)). I'm tying to see if there is a change over time in construct variable.

My output does not show means for I and S
I also get an error ----> "e: operator invalid"

Any advice would be wonderful!

Syntax

sem (RBY1 <- I@1 S@1 _cons@0) ///
(RBY4 <- I@1 S@2 _cons@0) ///
(RBR2 <- I@1 S@3 _cons@0) ///
(RBR3 <- I@1 S@4 _cons@0), ///
latent (Intercept Slope)
var(e.RBY1@var e.RBY4@var e.RBR2@var e.RBR3@var) ///
means(intercept slope)