st: Finite mixture model (FMM) estimation of probability determinants

["Julia Frances Slejko" <slejko@uw.edu>]

Hi,
I am using FMM to estimate a mixture of two normal distributions.  I have
been able to get the parameter estimates and the posterior probabilities
themselves.  Now, I would like to use the Model 2 statement cited in the FMM
help doc to estimate the determinants of the posterior probabilities.
I have used the syntax as described in FMM help:

fmm y x1 x2 x3 x4, comp(2) mix(normal) prob(x1 x2 x3 x4)

But I get the following error: 'provide starting values or estimate 2
component Normal model with constant component probabilities'.

Must I do this in two steps?  Is it OK for both var lists to be identical?
The FMM help does not address starting values so I am not sure how to do
this.

Any suggestions?

Thank you,
Julia
--
Julia F. Slejko, PhD
Postdoctoral Fellow

Pharmaceutical Outcomes Research and Policy Program
School of Pharmacy | University of Washington
Box 357630 | Seattle, WA 98195-7630
mobile 720.937.9605
fax 206.543.3835
slejko@uw.edu


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