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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 


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 zvalue. 

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