I have 2 groups (same students,two points-T1/T2). They were measured in the same 2-factor scale. My ds is in the long format (u1 u2, ..., grp) I want to perform a growth and invariance analysis,compute fscore for each person at T1 and T2 and, after plot. T2 must consider T1. The demo of my code:
NAMES ARE u1-u6 g; USEVARIABLES ARE u1-u6; CATEGORICAL ARE u1-u6; GROUPING IS g (1=year3 2=year4); ANALYSIS: PARAMETERIZATION = THETA; ESTIMATOR = WLSMV; MODEL: f1 BY u1@1 u2 (f21) u3 (f31); f2 BY u4@1 u5 (f52) u6 (f62); [u1$1] (t1); (etc) f1*; f2*; f1 WITH f2*; [f1@0]; [f2@0]; u1@1; u2@1; (ETC) MODEL year4: f1 BY u1@1 u2 (f21) u3 (f31); f2 BY u4@1 u5 (f52) u6 (f62); [u1$1] (t1); [u2$1] (t2); (ETC) f1*; f2*; f1 WITH f2*; [f1*]; [f2*]; u1@1; u2@1; (ETC) OUTPUT: TECH1; STDYX; savedata: file is fscores.dat; save=fscores;
Just one group measured twice. The same student was measure last year and this year with the same scale. I was following Millsap and Yun-Tein's instructions and that´s that's the why I modeled like that. Could you please link some help file. Thanks again for all support.
With a single group measured twice you would not use the Grouping option. Grouping is for independent observations which would not be the case with the same subject measured twice. Instead, use a regular single-group analysis where you analyze 2*p outcomes where p is the number of outcomes at each of the 2 time points. The measurement invariance testing can still be done (across time).
Luis FCA posted on Saturday, February 10, 2018 - 10:37 am
Using UG ex 6.14, you get an estimated growth means plot by
Plot: type = plot3; series = f1-f3(s);
and then requesting Estimated means.
There is no automatic way of getting estimated growth plots for the factor indicators. You would have to express their means over time using model parameter labels in Model Constraint and use the LOOP and PLOT options.
Luis FCA posted on Thursday, February 15, 2018 - 3:57 am
Thanks much, Dr. Muthen! All questions are clear now!