Re: st: consecutive years

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Mon, 18/10/10, Biljana Dlab wrote:
> However this code results that for some firms I have two
> (or more) strings with consecutive years - both these strings are 4
> or more consecutive years long. 
> I would like to indentify such a cases and I would like to
> keep both (all) string, but under modified "firm" (i.e. original firm
> number + 1)

In that case I would typically create another id variable, one identifying
firms, and a new one identifying spells. This is how I would do that:

*--------------------- begin example ---------------------
clear
input firm    year    corr        run13    maxrun13
31    1991    -0.5604    1    6
31    1992    -0.5604    2    6
31    1993    -0.5604    3    6
31    1994    -0.5604    4    6
31    1995    -0.5604    5    6
31    2000    -0.5604    1    6
31    2001    -0.5604    2    6
31    2002    -0.5604    3    6
31    2003    -0.5604    4    6
31    2004    -0.5604    5    6
31    2005    -0.5604    6    6
end

tsset firm year
gen break = L.firm == .
bys firm (year) : gen spellid = sum(break)
list
*-------------------- end example ----------------------
(For more on examples I sent to the Statalist see: 
http://www.maartenbuis.nl/example_faq )

If you want you can combine the two id-variables into a single
one using -egen long newid = group(firm spellid), label-

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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