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# st: gllamm with numerical problems and the setup with discrete latent vars

 From Hey Sky To statalist Subject st: gllamm with numerical problems and the setup with discrete latent vars Date Thu, 6 May 2010 09:37:23 -0700 (PDT)

```hey, all

just read the "ML numerical problems" and thought the problem I met

I am modeling training behavior with discrete latent variable. I assume there is
only one discrete latent variable, and the code is as following. it works well.

gen cons=1
eq mu1: cons

gllamm training_decision indep,  i(id) base(5) link(mlogit) family(binom) ip(f) nrf(1) eq(mu1)

the result of upper code for latent variable:
Probabilities and locations of random effects
------------------------------------------------------------------------------
***level 2 (id)

loc1: -1.8365, .54899
var(1): 1.0082459
prob: 0.2301, 0.7699

my understanding to the loc1 is: the parameters for the discrete latent variable, type of person,
for all people. that is:

epsilon_i= alfa_0 + alfa_1*mu
mu is type of person which I assume two types here.

but how to model it if  I assume people with different training decision have
different probility to belong to type 1 or 2 person?

I have tried the following code and hope I can get:
epsilon_i= alfa_edu_0 + alfa_edu_1*mu
epsilon_i= alfa_wrk_t0 + alfa_work_t1*mu
epsilon_i= alfa_wrknt0 + alfa_wrknt1*mu

the code:
eq mu1: training
eq mu2: work_with_training
eq mu3: work_no_training

gllamm training_decision indep,  i(id) link(mlogit) family(binom) ip(f) nrf(3) eq(mu1 mu2 mu3)

but the computer reports numerical problems. I think some place in the code is wrong,
because of fortran have given result. any suggestions about it?

I wish I make myself clear and thanks a lot for any reply in advance

Nan
from Montreal

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