TITLE: LGM with categorical outcomes: Delta parameterization
DATA: File is Duncan_101.dat;
VARIABLE: Names are Y1 Y2 Y3 Y4;
Usevar = Y1-Y4;
Categorical are Y1-Y4;
ANALYSIS: !model=nomeanstructure;
MODEL: i BY Y1-Y4@1;
s BY Y1@0 Y2@1 Y3@2 y4@3;
[Y1$1 Y2$1 Y3$1 Y4$1] (T1);!thresholds held equal across time points
[Y1$2 Y2$2 Y3$2 Y4$2] (T2);
{y1@1.0 y2* y3* y4*}; !differences in variances of the outcome over time
!are represented by allowing scale parameters to vary over time
OUTPUT: tech1 tech3 tech4 sampstat standardized;