st: Using -exapand

[James Bernard <jamesstatalist@gmail.com>]

Hi,

I am trying to use -expand to replicate observations:

Focalfirm   Technology  year        n	
-------------    --------------   ---------   -------------

Toyota	XYZ    	1990 	1	
Toyota	XYZ	        1991 	4	
Toyota	ZZZ	        1990		--
VW   	ABC   	1999	        2
VW   	CDE  	1998	        3


The idea is that I want to repeat each observation n times. However,
the new observation must have an updated year number too. That is, the
second observation must be repeated 4 times (including the original
observation, of course), but the year must be updated. So, the next
observations would be identical to the original one, except that their
year will be 1992, 1993 and 1994.

Using -expand,

-expand n, generate(id)

this is what I get


Focalfirm	Technology	year	n	id
Toyota	XYZ	               1990 	1	0
Toyota	XYZ	               1991	4	0
Toyota	ZZZ	               1990		0
VW	       ABC	               1999	2	0
VW	       CDE	               1998	3	0
Toyota	XYZ	               1991	4	1
Toyota	XYZ	               1991	4	1
Toyota	XYZ	               1991	4	1
VW	       ABC	               1999	2	1
VW	      CDE	               1998	3	1
VW	      CDE	               1998	3	1



This is fine, except that the years are not updated. Any idea how I can do this?

Thanks,
James
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