use COW direct contiguity data

[davcl]

from Feb 2020 email...

any suggestion on how to use this? We can hypothesize that bordering or nearby states will more quickly establish symmetric ties versus those without shared borders. Shared borders can be put in place as dummy variables- like is there a shared land border or not. This would eliminate the region variable in some ways, which is good because region classifications are easier for reviewers to nit-pick.

we use land and water boundaries? We can determine whether the states share a land border or is separated by water.

what's the distance cutoff for water?
I think for the distance by water, we can set it to Contiguity Type 3 (separated by 24 miles). Set it up as like a dummy variable for less than or greater than 24 miles.

[jmp243]

I think setting the water distance to 24 miles is good (ContType 3). I was re-reading the contiguity variable codebook. There has not been an update since we last looked at it. We will need to use version 3.2 contdir.csv: The master data file (with one entry per contiguity relationship). Thinking about what it means to be 24 miles and not 150 miles apart, theoretically.

[jmp243]

contdir.csv is the master data whereas contdird is a dyadic data. But if there is going to be more network stuff it may not suffice to look at dyadic data only. Although diplomatic exchange can only be dyadic.