Re: st: Data Expansion Question

[wgould@stata.com (William Gould, StataCorp LP)]

David Lektzian <david.lektzian@ttu.edu> writes about expanding a
cross-sectional time-series dataset.  He writes, 

> This is the way the original data looks:
>  
>        Unique id    duration     count      year   [...]
>                1           4         1      1990   [...]
>                2           3         1      1995   [...]
> 
> I want to expand the data to look like this:
>
>        Unique id    duration     count      year   [...]
>                1           4         1      1990   [...]
>                1           4         2      1991   [...]
>                1           4         3      1992   [...]
>                1           4         4      1993   [...]
>                2           3         1      1995   [...]
>                2           3         2      1996   [...]
>                2           3         3      1997   [...]

Try the following:

     1.  Make above example:

          . input caseid duration count year 
          . 1 4 1 1990 
          . 2 3 1 1995
          . end

     2.  Solution:

          . expand duration 
          . sort caseid
          . by caseid: replace count = _n
          . replace year = year + count - 1 
          . list

-- Bill
wgould@stata.com
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/