st: Sorting relationship dates to get a correct chronological sequence

[Anna Reimondos <areimondos@gmail.com>]

Hello

I am having trouble thinking of a way to sort my data they way I would like to.

What I am trying to do is to sort people's relationships in the
chronological order that they happened.

I have separate pieces of information about the start and end dates of
all 1) cohabitations 2) marriages.

EXAMPLE
A person might have had 5 relationships:  3 cohabitations and 2
marriages. The second marriage is still ongoing.
 In long format the data looks like:

Person    Relationship                 Star Year     End Year
1             Cohabitation 1              2001             2001
1             Cohabitation 2              -1 missing    -1 missing
1             Cohabitation 3              -1 missing     -1 missing
1             Marriage 1                    1998              2000
1             Marriage 2                     2008            -20 (Ongoing)


I have tried sorting the data by start year, to get the chronological
order correct but obviously run into problems with the relationships
that have missing start or end dates since these have negative values
and therefore appear first, as such:

Person  Relationship                 Star Year     EndYear
1             Cohabitation 2              -1 missing    -1 missing
1             Cohabitation 3              -1 missing     -1 missing
1             Marriage 1                    1998              2000
1             Cohabitation 1                2001            2001
1             Marriage 2                     2008            -20 (Ongoing)


However, this is wrong because obviously Cohabitation 2 and
Cohabitation 3 must have occured *after* Cohabitation 1.
The actual correct order I am trying to achieve is : Marriage 1,
Cohabitation 1, Cohabitation 2, Cohabitation 3, Marriage 2.
I was hoping someone would have a suggestions of how I could achieve
the correct sequence. I think I will have to use a loop maybe?


Thanks a lot,
Anna

(Using STATA 11.1 Windows)

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