Re: st: Keep observations in panel data

[Nick Cox <njcoxstata@gmail.com>]

You're right. That was silly of me.

A crude but I hope improved solution is

bysort id (year) : keep if
(subsidy == 1 & subsidy[_n+1] == 0 & subsidy[_n+2] == 0) |
(subsidy == 0 & subsidy[_n-1] == 1 & subsidy[_n+1] == 0) |
(subsidy == 0 & subsidy[_n-2] == 1 & subsidy[_n-1] == 0)

Nick

On Tue, Jan 18, 2011 at 3:19 PM, s <s.afcha@ub.edu> wrote:
> Dear s or S:
> This sounds like
> bysort id (year) : keep if subsidy == 1 & subsidy[_n+1] == 0 &
> subsidy[_n+2] == 0
> Nick
> P.S. as a native English speaker, frequent reviewer and Editor, I
> advise firmly against the English usage "a panel data", which does not
> qualify as standard. (It seems mildly viral recently, but I'm not
> deflected by that.)
>
>
> Dear Nick,
>
> Thanks for your help, but I am implementing your solution and it only keep
> the information for the
> year in which subsidy==1. I also need the information for the rest of the
> years. In the example,
> the data corresponding to firm 1 for the years 2001, 2002, 2003 and 2004.
>
> id year subsidy
>  1 2000   0
>  1 2001   0
>  1 2002   1
>  1 2003   0
>  1 2004   0
>  1 2005   1
>  2 2000   0
>  2 2001   0
>  2 2002   1
>  2 2003   1
>  2 2004   0
>  2 2005   1
>  3 2000   1
>  3 2001   1
>  3 2002   1
>
> Sergio
>
> P.S. I will take note of your observation about panel data.
>

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