Re: st: margins at every observation

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Tue, 12/10/10, Thomas wrote:
> I want to calculate the marginal effects for all
> observations:
> 
> sysuse auto, clear
> reg price c.mpg##c.mpg
> 
> gen dydx = _b[mpg]+2*_b[ c.mpg#c.mpg]*mpg
> 
> I thought I would get the same using:
> 
> margins, dydx(mpg) at((asobserved) mpg)
> 
> but I only get a single value at the mean of mpg.
> 
> How can I get the marginal effect at each observation from
> -margins- (if at all)?

That marginal effect only depends on the value of mpg, so 
you can get a complete list of all marginal effects by typing:

margins, dydx(mpg) over(mpg)  

There is no -generate- or -replace- option in -margins, so there
is no easy way to turn this into a variable (it is possible, but
your manual computations are just easier).

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------




      

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