I am analyzing a dataset that incorporates a directed-dyad year unit of analysis. But, for the past week or so, I have been struggling to think of how to code a condition based on the values of the directed dyad-years. (I assuming this is the port of call, since this is a bit of a logic game).
The dyads are cities. Let’s call them City I and City II. The city codes are numerical.
I am trying to come up with a way to code for a variable “Z” depending on the values of one member of the dyad. Variables A-D, Y and Z are all coded as "." “0” or “1.” If there is nothing coded for A-D, then Y=0.
The following are the rules for the condition, using the example of the small dataset seen below:
Code:
* Example generated by -dataex-. To install: ssc install dataex clear input byte(city1 city2) int year byte(a b c d y z) 10 11 1990 1 . 1 . 1 0 11 10 1990 1 . 1 . 1 0 10 12 1990 . . . 1 1 0 12 10 1990 . . . 1 1 0 11 12 1990 . . . . 0 1 12 11 1990 . . . . 0 1 10 13 1990 . 1 . . 1 0 13 10 1990 . 1 . . 1 0 11 13 1990 . . . . 0 . 13 11 1990 . . . . 0 . end
Y is coded as “1” if at least one variable between A-D is coded as “1.”
If Y=1 for the dyad-year City 10 and City 11 in 1990 (and similarly for the directed-dyad year (City 11 and City 10 in 1990),
and if Y=1 City 10 and City 12 in 1990,
then, Z=1 if City 11 and City 12 in 1990, so along as Y=0 for the dyad City 11 and City 12 in 1990 (i.e. there is nothing coded for A-D).
In other words, these conditions are all dependent on the members of the dyad, and this is where I am struggling trying to put a condition together in Stata.
Essentially, I am trying to code CITY I (11) and City II (13) in the same way. For the dyad City 10 and 13 in the year 1990, Y=1. City 10 and City 11, Y=1. I am trying to code City 11 and City 13 as Z=1, given also the fact that they (City 11 and City 13) have no values for A-D (hence, Y=0).
Thank you in advance for any help.
0 Response to Problem with Conditions
Post a Comment