Mapping Hacks

Geocode a U.S. Street Address #79

Chapter 7, Names and Places

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HACK

as a “freebie.” And then they decided that geocoding had added value, and

one by one they pulled the plug.

There is a strong movement of people who believe in open data and open

data formats. Mapping sites’ removal of free geocoding led directly to the

creation of the free geocoder.us site. As William Gibson famously noted,

“the street finds its own uses for things,” and that use can transcend and

exceed the original vision of the tool.

The Birth of geocoder.us

Strangely enough, the removal of useful features from online map services

seemed to occur right before a surge of interest in free sources of geodata

occurred among the free and open source software community.

Collecting this data and keeping it up to date with “ground truth squads”

who go around and verify that streets are where they are supposed to be and

that houses haven’t up and run off, is quite expensive.

An alternative to the full expense of this data lies in the U.S. Census Bureau.

They have compiled TIGER (Topologically Integrated Geographic Encod-

ing and Referencing system) data. TIGER data is used as part of the normal

fulfillment of their duties to do an actual enumeration of the people every 10

years. This data is imperfect, but the regular tasks of census workers are sim-

ilar to our own needs. They wish to identify the location of a residence

based on a street ...