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Hello, I have just run a LTA model assuming invariance across time (3 waves). In order to understand better the meaning of the classes I have tried to obtain the estimated itemresponse probabilities for the respective observable variables categories (in my case 1 and 2). But, I haven't been able to find them. I have only got the class pattern thresholds. Is there any way to get those probabilities (itemresponse)? Thank in advance, Sebastian 


What I am trying to get using MPLUS is something like this (for a LTA model): Rho estimates (itemresponse probabilities): (All times) Response category: 1: Status: 1 2 3 tab1 : 0.0191 0.9319 0.7290 alc1 : 0.1394 0.9419 0.7190 mar1 : 0.0050 0.9215 0.0224 coca1 : 0.0014 0.1752 0.0052 Response category: 2: Status: 1 2 3 tab1 : 0.9809 0.0681 0.2710 alc1 : 0.8606 0.0581 0.2810 mar1 : 0.9950 0.0785 0.9776 coca1 : 0.9986 0.8248 0.9948 I got this output from SAS (PROC LTA). Thank you. 


You would need to compute the probabilities yourself in this case: prob = 1 / (1 + exp(threshold) 


Thank you Linda for your reply. I am new in Mplus and now I am trying to explain the transition probabilities using covariates. Following the example 8.13 (covariate and interaction) in the UG, I have tried this model: CLASSES = c1(3) c2(3); MODEL: %OVERALL% c2 ON c1 male; c1 ON male; I assume measurement invariance across times (in my example two waves). My problem is that I don't know how to exactly interpret the coefficients. I want for example to get the odds ratio of moving from class 1 (time 1) to class 2 (time 2) between males and females, but I am not sure which coefficient represents that figure in the output. Could you give me any clues? Thank you in advance, Sebastian 


Here is the output: Categorical Latent Variables C2#1 ON C1#1 4.377 0.408 10.729 0.000 C1#2 2.243 0.616 3.642 0.000 C2#2 ON C1#1 0.081 0.197 0.412 0.680 C1#2 2.764 0.459 6.020 0.000 C2#1 ON MALE 0.372 0.140 2.648 0.008 C2#2 ON MALE 0.358 0.140 2.546 0.011 C1#1 ON MALE 0.629 0.098 6.433 0.000 C1#2 ON MALE 0.706 0.149 4.733 0.000 Intercepts C1#1 0.628 0.072 8.686 0.000 C1#2 1.340 0.141 9.479 0.000 C2#1 2.829 0.380 7.455 0.000 C2#2 1.427 0.147 9.677 0.000 


See the Nylund dissertation on the website. Please keep your posts to one window. 


Thank you Linda. There is not an explanation of a model like 8.13 (UG) in the Nylund dissertation: LTA WITH A COVARIATE AND AN INTERACTION. Regards. 


In Example 8.13, the interaction is c ON x varying across the classes of c1. You need to use the information in the dissertation to generalize to other examples. 

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