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 Nicole R. Nugent posted on Tuesday, June 17, 2008 - 2:26 pm
I am conducting GMM to examine trajectories of smoking behavior across 3 timepoints.

DATA: file is smokers.dat;
VARIABLE: NAMES ARE vid new t1 t2 t3;
MISSING = all(-1234);
USEV ARE vid t1 t2 t3;
CATEGORICAL IS vid;
CLASSES = c(2);
ANALYSIS: TYPE = MIXTURE MISSING;
STARTS = 1000 20;
STITERATIONS = 20;
ALGORITHM = INTEGRATION;
MODEL:
%OVERALL%
i s | t1@0 t2@1 t3@2;
i s ON vid;
c#1 ON vid;
OUTPUT: standardized tech8 tech11 tech14;

I have read all of the GMM articles on the website and have two questions:

1. Based on theory and BIC/Entropy data I would select the 3 class model. Based on BLRT, the 2 class model would be preferred. Would you recommend using the BLRT?

2. How do I assess the influence of the covariate (vid)?

Thank you in advance -
Nicole
 Linda K. Muthen posted on Tuesday, June 17, 2008 - 2:34 pm
1. I would choose the one that makes the most sense substantively?

2. Do you mean how do you tell if the relationship is statistically significant? Column 3 of the output is the ratio of the parameter estimate to the standard error of the parameter estimate. This is a z-value.
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