Greetings,
I am working with a times-series cross-section data set where the unit
of analysis is the country-pair/year. The data include a dichotomous
variable indicated when a new policy was initiated. I also have a
variable that indicates of the duration of that policy (measured in
years). I need to create a variable that indicates when the policy was
in effect. For example, one cross-section my look like this:
Policy Policy Policy
Initiation length ongoing (new variable)
0 0 0
1 3 1
0 0 1
0 0 1
0 0 0
1 2 1
0 0 1
0 0 0
I need to create the "policy ongoing" variable.
I have tried generating a new variable, and then typing:
replace newvariable=L.newvariable+(policylength-1)+policyinitiation
This should work, but Stata tells me: (593368 real changes made, 593368
to missing); so all the values are replaced by missing values.
I am really stumped here, any help would be greatly appreciate.
Thanks,
Cooper
___________________________
A. Cooper Drury
Assistant Professor
Department of Political Science
University of Missouri
Columbia, MO 65211-6030
573-884-6747
www.missouri.edu/~drurya
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