-------- Original Message --------
Subject: Re: "Natural borders"
Date: Thu, 3 Nov 2011 17:41:22 GMT
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My sense of it is that it would still be fairly labor-intensive even
with GIS.  I attempted a similar project with U.S. Counties and had
limited confidence in my result.  You could possibly use segment length
as a heuristic -- short segments might indicate a natural border while
longer ones might indicate an arbitrary? artificial? man-made?
straight-line? border.  (I don't like any of those terms).  However
there would still be chance of a mistake.  A border might be straight
for a while and then have an unexplained notch - the notch might be
something natural like a ridge, or semi-natural like a canal, but it
might just be a property fence.  Long segments might indicate merely
sloppy digitizing rather than a true straight-line boundary.

Is the patron wanting a percent value or something?  A jagged stream is
going to contribute more length than a straight-line boundary.  Or is
each link (say Jordan-Iraq, Jordan-Israel, etc.) to be equally weighted,
with mixed boundaries getting appropriate values?

Joe McCollum
Forest Inventory and Analysis