st: expand and duration model

[ncdcta00@uniroma2.it]

Dear statalist,
I have a problem to understand  how to expand my observation to stset  
my data to use in a
duration model.
I have the following data set:

id  datealt          datebax          y          x
1    11/02/2001       14/08/2003      100       205
1    02/03/2005        05/06/2005     120       130
1    13/08/2005        18/12/2005      100        130
2..........
2..........

so I want  a dataset for the period that I don't observe the id:

id  datealt          datebax          y          x
1    11/02/2001       14/08/2003      100       205
1    15/08/2003        01/032005         0       0
1    02/03/2005        05/06/2005     120       130
1    06/06/2005        12/082005        0           0
1    13/08/2005        18/12/2005      100        130
2.........
2.......
2..........
Someone can help me?
I try with expandby but without results.
Thanks in advance.


Catia

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