Question
Dear Stata List!
I am working on a project that examines a firm's international strategic alliance (ISA).
In my huge dataset, I have around 2000 firms forming ISA between 01/01/1989- 0/01/1999. Each firm is likely to form multiple international strategic alliances during this period.
For example: Firm A forms the first strategic alliance on 01/02/1989; the second on 04/09/1990; the third on 06/09/1997.
What I need to record is the number of new strategic alliances that the firm forms within 5 years after the focal one.
For firm A, the number of new strategic alliances that Firm A forms within 5 years is 1 corresponding to its first strategic alliance on 01/02/1989;
the number of new strategic alliances that Firm A forms within 5 years is 0 corresponding to its second strategic alliance on 04/09/1990 ;
the number of new strategic alliances that Firm A forms within 5 years is 0 corresponding to its third strategic alliance on 06/09/1997;
As it is a huge dataset, I can't do it by hand. How can I do it by using STATA? Thanks!
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