Re: st: Error with ffirst in ivreg2

[Christopher Baum <kit.baum@bc.edu>]

<>
Please show us your logfile for that estimation, w/w/o ffirst option. Does the first option have the same problem?

Thanks
Kit

On Apr 6, 2011, at 2:33 AM, Abbie wrote:

> I am running a 2SLS specification with two endogenous variables and two instruments, plus state and year fixed effects.  One endogenous variable is the current period population and the other is the one year lagged population. The instruments are the IV for the current period and the previous period's instrument.
> 
> The first stage with one endogenous variable is strong, but I wanted to check that both instruments are strong predictors in the two instrument-two endogenous variable case.
> 
> When I run my specification using ivreg2 with the ffirst option, I get the error message "reduced form estimation failed." However, when I omit the ffirst option, the same specification runs and I get reasonable looking estimates.
> 
> Does anyone know what the problem is? It seems odd that ivreg2 would generate 2SLS estimates if the reduced form truly were not available so I don't understand why it runs without ffirst but not with it.


Kit Baum   |   Boston College Economics & DIW Berlin   |   http://ideas.repec.org/e/pba1.html
                              An Introduction to Stata Programming  |   http://www.stata-press.com/books/isp.html
   An Introduction to Modern Econometrics Using Stata  |   http://www.stata-press.com/books/imeus.html




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