Re: st: predicting y, with other variables

[Richard Williams <Richard.A.Williams.5@ND.edu>]

At 09:28 AM 5/22/2007, alessia matano wrote:
> Hi,
>
> I hope some of you can help me...
> I estimate a regression and I saved the coefficients e(b) in the
> corresponding matrix. Now I would like to apply these coefficients
> estimates to the same set of x's variables, but for one that I want to
> substitute with another and calculate the predicted values (to see
> which is the variation in the rpedicted values using this other
> variables). Anyone of you knows how to do this?
> I tried creating a matrix with the new x's variables, but my n=2400
> and so the matsize set does not allow me to create such a matrix.
>
> Thank you very much for your help.
> Regards
> alessia
I'm not totally sure I understand you alessia.  Is the idea that you 
want to do something like

reg y x1 x2 x3

but then substitute x4 for x3 when computing predicted values?  If 
so, try something like

clonevar tmpvar = x3
reg y x1 x2 tmpvar
predict yhat1
drop tmpvar
clonevar tmpvar = x4
predict yhat2


-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
OFFICE: (574)631-6668, (574)631-6463
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EMAIL:  Richard.A.Williams.5@ND.Edu
WWW:    http://www.nd.edu/~rwilliam

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