Address matching also commonly called ‘geocoding’ Very common for: –Crime reports –Customer records –Tax/Parcel records –911 systems Most common form of ‘geographic’ data (places are located without coordinates)

In order for address matching to work you must begin with TIGER files Topologically Integrated Geographic Encoding and Referencing Developed for the US Census Bureau, the best Base level street maps available.

A sample of a TIGER road file for Benton County Oregon.

Where and How to get TIGER files? ESRI has been distribuiting TIGER files in an easily accessible format for a number of years:

Arcview uses the address fields from the TIGER File to begin locating a given address. Before gecoding an address table, it is necessary to go into the theme/properties tab and set up the geocoding ‘address style’ field.

Rates of 35-45% of address correctly matched on the first try are fairly common.

To maximize the number of addresses automatically matched you should: Don’t use periods. Periods are ALMOST NEVER used (except when its part of the street name, which is very, very unusual); Don’t spell out street numbers (e.g. 14th St; NOT Fourteenth St); "W" for West and "E" for East (e.g. 215 W 118th St). However,"East"and "West" are spelled out when its part of the street name (e.g. West Side Hwy); "th" or "rd" or "st" contiguous with the street number, when appropriate (e.g. 215 W 118th St)

When addresses have been geocoded, it is possible to begin analyzing the spatial distribution of points, and relationships. In this example, veterinary clients are seen with median income as a backdrop.