Alex He posted on Sunday, February 08, 2015 - 10:06 am
I was working on Ex8.6 from the user guide. I wonder how I can interpret the thresholds associated with the distal outcome within each class. Take the output of Ex8.6 for example, for Latent Class 1, does -15 for U$1 indicate that the logit of getting the outcome "1" is -15? (Basically the odds are very very small). Does 4.194 associated with U$1 under Latent Class 2 indicate that the logit of getting a "1" is 4.194, which means the odds are very high?
A related question is why there is no significance test associated for the threshold for Latent Class 1? Is there a way in Mplus to statistically compare the thresholds of Class 1 and Class 2? Thanks!
I don't see those parameter estimates for UG ex 8.6, but let me answer in generalities. A threshold of -15 means that that the lowest category of the observed item has zero probability of occurring. A high logit of 4.194 implies a high probability for the lowest category.
You can test threshold equality by using Model Test,
0 = t1-t2;
where the t's are labels for the thresholds given in the Model command.