Hi all,
I have a data containing multiple spells per person. The spells are measured in
months.
The data is in the following form:
PERSON BEGIN END EVENT DUR
1 ( 0 1 ] 1 1
1 ( 4 13 ] 1 9
2 (15 25 ] 0 10
where variables BEGIN and END are measured in calendar time (1 refers to Jan
1995,
2 to Feb 1995 and so on until 60, Dec 1999).
I stset the data in the following way:
stset end, failure(event) time0(begin) exit(time .) origin(time begin)
which means I want to "set the clock to zero" at the start of each spell.
Now I would like to include a dummy for December months 12, 24, 36 and 48.
It is thus a time-varying variable getting value 1 for the December months and
0 for other months. A spell may include zero, one or many December months.
I suppose I should use stsplit and do some kind of episode splitting, but could
someone
help me and give me advice how I should do it with my data?
Thank you in advance.
Marjo Pyy-Martikainen
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