Re: st: How to 'predict' constant by region?

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

At 11:01 PM 8/6/2008, Galina An wrote:
> Dear statalist users,
> I was wondering if anybody encountered the following problem:
> when I run the following code, I need to save constants for different regions:
>
> by region: reg migration q1 q2 q3
> by region: gen constant=_b[_cons]
>
> However, I get the same constant for all regions.
> Can anybody give me a hint?
With the 2nd by command, you are not rerunning all the separate 
regressions.  Instead, the gen command just picks up the constant for 
the last region's regression.

You could use the -statsby- command.  Or, do something like

gen constant = .
levelsof region, local(levels)
foreach levl of local levels {
        reg migration q1 q2 q3 if region == `levl'
        replace constant=_b[_cons] if region == `levl'
}

I think there are some other handy utilities for such tasks but I 
forget what they are.


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Richard Williams, Notre Dame Dept of Sociology
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