Hello Dear Stata users,
In a presentation prepared by C. Baum (see the site
http://fmwww.bc.edu/ec-c/s2009/771/DIWMar2008.beamer.pdf, page 38),
it is said that it is possible to restrict certain instruments to
enter certain first-stage regressions by specifying a full
simultaneous system of equations and by using the command "reg3". As
far as I know in "reg3", all instruments specified in option exog( )
are used in reduced form regressions. Does anybody know how to do
Baum's suggestion ?
More concretely, I am currently estimating a demand system using AIDS
model. Prices (P1, P2 etc.) are assumed to be endogenous. I assume
instrument IV1 is correlated with P1, but I do not want to use IV1 for
P2, for example.
Thank you.
Ekrem Kalkan
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/