try this...
gen nyears=0
label variable nyears "Number of years country has nukes"
sort ccode
gen nukeyear=year*nukes
by ccode: egen minyear=min(nukeyear) if nukeyear>0
by ccode: replace nyears=year-minyear+1 if nukeyear>0
drop nukeyear minyear
- Paul Millar
Sociology
University of Calgary
At 03:14 PM 02/04/2005, you wrote:
To whom it may concern:
I have a time series dataset organized by country year, with one entry per
year per country. I want to create a count variable that measures the
number of years it has been since a given country has acquired nuclear
weapons, the variable of interest for my study. But I am having trouble
getting the coding entirely right. The variables that I "think" matter
here are:
-ccode: the country code for each country
-nukes: a binary variable that is 0 if a country does not have nuclear
weapons and a 1 if it has nuclear weapons
-year: this is pretty obvious. .
The current coding I have is:
gen nukecount=0
replace nukecount=(nukecount[_n-1]+1) if ((ccode==ccode[_n-1]) &
(nukes==1) & (nukes[_n-1]==1))
If anyone has some advice about what I am doing wrong and how to
potentialy correct it. . that would be fantastic and I would really
appreciate it.
Sincerely,
Michael Horowitz
*******************************************************************************
Michael Horowitz
78 Kirkland Street, #1
Cambridge, MA 02138
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