st: Re: Re: RE: Re: eliminate negative values and their positivecounterpart

["Michael Blasnik" <michael.blasnik@verizon.net>]

I thought of mentioning that as a possibility to see if the original post 
was concerned about that possibility.  It actually would not be too hard to 
change my code to only eliminate matched pairs if that is required.

Michael Blasnik

----- Original Message ----- 
From: "Sergiy Radyakin" <Radyakin@aoek.uni-hannover.de>
To: <statalist@hsphsun2.harvard.edu>
Sent: Tuesday, March 06, 2007 4:53 PM
Subject: st: Re: RE: Re: eliminate negative values and their positive 
counterpart



> Sorry, (my mistake) this line should be simply omitted. Both npos and nneg 
> are defined later on.
> I guess the solution proposed by Mr Blasnik will exclude observations if 
> the sum
> over a group is zero, but should it be a necessary condition?
>
> 30
> -30
> 30
>
> (with all other variables being same) --  e.g. bought apples for 30, than 
> returned them to the cashier, than decided to buy them again :)
> This should simplify to 30, but the sum over the group is not 0.
>
> it is a pity that I can't do as I have written, i.e. -count if- 
> after -egen-
>
> Sincerely yours,
>   Sergiy Radyakin
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