Re: st: RE: AW: dealing with duplicate "pairs" of columns

 From "Vitorino, Maria Ana" To "statalist@hsphsun2.harvard.edu" Subject Re: st: RE: AW: dealing with duplicate "pairs" of columns Date Thu, 11 Feb 2010 03:02:07 -0500

```Thanks Nick!

Maria Ana

On Feb 10, 2010, at 9:05 AM, "Nick Cox" <n.j.cox@durham.ac.uk> wrote:

>
> SJ-8-4  dm0043  . Tip 71: The problem of split identity, or how to
> group
>        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  N.
> J. Cox
>        Q4/08   SJ 8(4):588--591                                 (no
> commands)
>        tip on how to handle dyadic identifiers
>
> Nick
> n.j.cox@durham.ac.uk
>
>
> Martin Weiss
>
> clear*
>
> input byte(Person1_id ClosestPerson  Person1_age)
> 1            2            10
> 2            1            20
> 3            1            30
> 4            3            40
> end
>
> gen lower=min( Person1_id, ClosestPerson)
> gen upper=max( Person1_id, ClosestPerson)
> bys lower upper ( Person1_age): gen byte dup=!(_N==1)
> by lower upper ( Person1_age): replace dup=2 if _n==_N &dup!=0
> l, noo
>
> Vitorino, Maria Ana
>
> I was wondering if there was a relatively simple way to achieve the
> following:
>
> My data looks like this:
>
> Person1_id ClosestPerson  Person1_age
> 1            2            10
> 2            1            20
> 3            1            30
> 4            3            40
> ...
>
> What I would like to do is to signal "duplicate" rows for which
> Person1
> is
> the oldest. Since this is hard to explain, the resulting data would be
> for
> the example above:
>
> Person1_id ClosestPerson  Person1_age  dup
> 1            2            10
> 1
> 2            1            20
> 2
> 3            1            30
> 0
> 4            3            40
> 0
> ...
>
> Note that the column dup has the following coding:
> dup=1 if there is another pair of ppl identical to the one in this row
> and
> Person1 is the youngest of the pair
> dup=2 if there is another pair of ppl identical to the one in this row
> and
> Person1 is the oldest of the pair
> dup=0 if there is no other pair of ppl identical to the one in this
> row
>
> *
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*
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```