matrix &non-pos def 1st der... PreviousNext
Mplus Discussion > Latent Variable Mixture Modeling >
 John D. Baser posted on Thursday, October 07, 2010 - 7:29 pm
Hi. I am doing discrete LCA with freq. wt
for 3 binary indicator variables specified. The freq wts are quite large,
in the thousands.
For no of classes >2, I am
getting either the error: ' standard errors may not be trusted since got non-positive definite 1st derivative matrix, prob with param #'with a cond #, or '
avoided singular info matrix by setting
params #, #. Are you using Newton_Raphson
to maximize the total likelihood? Can I
trust the value of params & their p-values if condition # is above a certain threshold? How do I treat the params that were fixed? The first error is more serious isn't it? Thanks for your help.
 Linda K. Muthen posted on Friday, October 08, 2010 - 2:39 pm
With three binary indicators, a model with more than three classes is not identified.
 John D. Baser posted on Friday, October 08, 2010 - 3:17 pm
I am getting these warnings & errors mentioned above
for 3 class models. I want to pick the most
stable solution, taking entropy into consideration.
How low does the condition # get before you
consider it ill-conditioned?
Can I trust the values of the parameters that have
been fixed?
 Linda K. Muthen posted on Friday, October 08, 2010 - 5:11 pm
Please send the full output for the three class model and your license number to
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