st: How to generate id numbers when expanding data

[Dick Campbell <dcamp@uic.edu>]

For teaching purposes I have created a table of results from an imaginary 
experiment as shown below.


     +----------------------------------+
     | wave   cond   sex    n   outcome |
     |----------------------------------|
  1. |    1      1     1   25        50 |
  2. |    2      1     1   18        49 |
  3. |    3      1     1   15        51 |
  4. |    1      2     1   25        50 |
  5. |    2      2     1   20        55 |
     |----------------------------------|
  6. |    3      2     1   19        54 |
  7. |    1      3     1   25        50 |
  8. |    2      3     1   16        58 |
  9. |    3      3     1   14        53 |
 10. |    1      1     2   25        50 |
     |----------------------------------|
 11. |    2      1     2   19        51 |
 12. |    3      1     2   17        50 |
 13. |    1      2     2   25        50 |
 14. |    2      2     2   21        57 |
 15. |    3      2     2   20        56 |
     |----------------------------------|
 16. |    1      3     2   25        50 |
 17. |    2      3     2   17        56 |
 18. |    3      3     2   15        54 |
     +----------------------------------+

The variable labeled "outcome" is a cell mean and I will expand the table 
by n cases for each cell.
 I will subsequently manipulate these data by adding random error to the 
outcome variable ,
adding covariates etc.

However, when I eventually analyze the data I need a unique id number for 
each case such that each record has an id
number which stays constant across waves so that I can use XT-series routines.
So, the expanded data set should look like this.


     +----------------------------------+
     |id wave   cond   sex      outcome |
     |----------------------------------|
  1. |1   1      1     1             50 |
  2. |1   2      1     1             49 |
  3. |1   3      1     1             51 |
  4. |2   1      1     1             50 |
  5. |2   2      1     1             55 |
     |----------------------------------|
  6. |2   3      1     1             54 |
  7. |3   1      1     1             50 |
  8. |3   2      1     1             58 |
  9. |3   3      1     1             53 |
 10. |4   1      1     1             50 |
     |----------------------------------|
 11. |4   2      1     1             51 |
 12. |4   3      1     1             50 |
 13. |5   1      1     1             50 |
 14. |5   2      1     1             57 |
 15. |5   3      1     1             56 |
     |----------------------------------|
 16. |6   1      1     1             50 |
 17. |6   2      1     1             56 |
 18. |6   3      1     1             54 |

etc through the 361 records implied by the data. Within
each combination of sex and cond there should be n cases
with an id that stays constant across waves.

I can not seem to figure out how to do this. I would guess that
-expandcl- should accomplish what I want, but I can't figure out
how to set it up. Perhaps there is some other clever solution.
If I were in SAS I would just loop over n with an -output- statement
and retain the counter as an ID. But I am a bit stymied here.


Dick Campbell
Univ. of Illinois at Chicago

  

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