Hacks 78-86

It is not down in any map; true places never are.

Herman Melville, Moby Dick

Apparently, human beings are pretty bad at naming things; sometimes we can't even agree how to agree that we're talking about the same object. However, we're quite good at filtering differences and recognizing identities: "Avenue," "Av," "Ave," and "Ave." are all apparently the same street suffix.

There are strategies for naming places to help humans and machines compensate for each others' weaknesses and provide practical assistance to one another. There are many standard code systems in the world, which unambiguously map a place to a location identified by the code. In the United States, the ZIP and ZIP+4 postal codes allow us to do good-enough, near-enough geolocation. Most countries have a postal code that identifies specific areas at some level of resolution.

For identifying countries and connecting regions and towns to them, there are the U.S. FIPS codes and the two- and three-letter ISO codes, which allow us to take different spellings, or different versions of country names, and unambiguously identify the same "place" being talked about.

Sadly, not many countries have the open geographic data policy maintained by the U.S. Census Bureau and Geological Survey, so a lot of world-mapping resources described in this chapter are dependent on data provided by the U.S. government. Local names for places may be "overwritten" by their U.S. English variants on world maps. Databases of postal codes and of street addresses are only available at a handsome price for an annual licenseout of the hands of the keen, amateur, free-GIS hacker.





Mapping Hacks
Mapping Hacks: Tips & Tools for Electronic Cartography
ISBN: 0596007035
EAN: 2147483647
Year: 2004
Pages: 172
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