Dear Statalisters,
I hope you all are doing well. I am having some problems to get my
model to converge. It does converge for some subsamples but generally
the models do not converge.
I am estimating a covariate measurement error model using gllamm. The
measurements of the latent factor are dichotomous variables (so the
measurement model is a two parameter item response model). The outcome
model is a discrete time duration model, which I am estimating by
expanding the data according to the duration variable. I am
particularly interested in the factor loading on the latent variable
z3.
Once the dataset is reshaped and expanded the commands for the
estimations look like the following:
***************************************************************************
***************************************************************************
ge z_x1 = z3*x1
ge z_x2 = z3*x2
ge z_x3 = z3*x3
ge z_x4 = z3*x4
*** Latent Equation and True Covariate model
eq latentfactors: z1 z2 z3
eq truecovariatemodel: x1 x2 x3 x4 x5
*** Outcome model
gllamm y z1 z2 z3 z_x1 z_x2 z_x3 z_x4 , ///
i(kids_id) eqs(latentfactors) link(logit logit) family(binom binom) ///
lv(measuredis) fv(measuredis) geqs(truecovariatemodel)
***************************************************************************
***************************************************************************
I would really appreciate some advice or general tips about convergence.
Thanks a lot already to everyone and have a good Sunday
marco.
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