Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: Add constraints in biprobit


From   [email protected]
To   [email protected]
Subject   st: Add constraints in biprobit
Date   Tue, 20 Jan 2004 10:48:57 -0500 (EST)

Hi, all,

I am using biprobit to estimate a bivariate probit model with some
nonlinear constraints on parameters. I have two questions:

1. The iterations go fine with the "fitting comparison model" stage. But
when the procedure goes to the "Fitting full model" stage, it says
"Constraints invalid: not possible with test". Is that I have to specify
linear constraints instead of nonlinear ones?

2. I also have to add some constraints on the rho, correlation between two
equations. How do I write the "rho" explicitly when defining the
constraints? Thanks.


*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2024 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index