Thursday, December 8, 2011

CraigsZips




Some time ago a fellow on LinkedIn found the United States of Craigslist useful as a targeted marketing reference (which is awesome!) and wondered if we had a list of the zip codes within each Craigslist zone.  A set of geometries is nice, but a list of zip codes is one big step closer to making big-ish data actionable.

Here is a look-up table of that association...

...and here is a map of that look-up table of that association...

Poster Print
You can order this map as a poster print to showcase your econo-geekery proudly on the wall of your choosing.


Background
Zip codes are weird, but then again so are the Craigslist zones (well, more hypothetical than weird).  Using a centered-within association in SQL Server 2008, (though this could have been done in R or Oracle, or GRASS, whatever) we were able to compile a list of which zip codes were centered within each Craigslist zone.

Reconciling two geometries to each other is a dark art.  The centered-within association was good enough in this case because we weren't reconciling any metrics (like demographics) in addition to the shapes.  But if you do have data within them that you'd also need to reconcile, it can be tempting to go down all sorts of roads that attempt to divvy up data by what proportions of one fall into the other.  Anyways...


4 comments:

  1. just what i needed! thanks mucho!

    ReplyDelete
  2. SPLENDID! Your favorite beverage is due, a few dozen times!

    ReplyDelete
  3. Anybody know of a similar source for Craigslist Canadian markets by postal code?

    ReplyDelete