# st: question

 From Scott Cunningham To statalist@hsphsun2.harvard.edu Subject st: question Date Wed, 2 Nov 2005 21:27:47 -0500

I am estimating a hazard, but I am missing data for certain time- variant covariates when t is very small. Seeing data will help me explain this.

+--------------------------------+
| sr _st _d _t _t0 |
|--------------------------------|
1. | . 1 0 1 0 |
2. | . 1 0 2 1 |
3. | . 1 0 3 2 |
4. | . 1 0 4 3 |
5. | . 1 0 5 4 |
|--------------------------------|
6. | . 1 0 6 5 |
7. | . 1 0 7 6 |
8. | . 1 0 8 7 |
9. | . 1 0 9 8 |
10. | .9738716 1 0 10 9 |
|--------------------------------|
11. | 1.081043 1 0 11 10 |
12. | 1.21261 1 0 12 11 |
13. | 1.125889 1 1 13 12 |
14. | . 1 0 1 0 |
15. | . 1 0 2 1 |
|--------------------------------|
16. | . 1 0 3 2 |
17. | . 1 0 4 3 |
18. | . 1 0 5 4 |
19. | . 1 0 6 5 |
20. | . 1 0 7 6 |
|--------------------------------|
21. | . 1 0 8 7 |
22. | . 1 0 9 8 |
23. | .9738716 1 0 10 9 |
24. | 1.081043 1 0 11 10 |
25. | 1.21261 1 0 12 11 |
|--------------------------------|
26. | 1.125889 1 0 13 12 |
27. | 1.080463 1 0 14 13 |
28. | .9527455 1 1 15 14 |

Notice that for all values of t=0 to t=9, I am missing data for sr. My first question is when I -streg-, what effect does this have on my estimation? None of my respondents complete their respective spells prior to t=10. Secondly, assume I wanted to fill in those missing values with the same value as t=10. How would I do this?

sc
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