emanuela,
i have done this in the past by writing a program to (1) run the first
stage regression and then (2) plug the predicted values into the second
stage equation -- 
and then after that program's written, using the bstrap command to obtain
bootstrapped standard errors for the program output.
chris
On Mon, 1 Sep 2003, E Randon wrote:
> Dear Statalist,
> 
> I would like to use non linear two stage least squares, but I can not
> find this command in the Stata Manual. Any suggestion? Many Thanks
> 
> Emanuela Randon
> 
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