Address Geocoding

1
Address Geocoding

• Engineering Applications of GIS
• Civil and Environmental Engineering
• CEEn 514

2
Definitions

• Adding an event theme allows you to create a
  point shapefile from a table of x-y values.
• Geocoding is the process of converting a set of
  street addresses to x-y values so that like an
  event theme a point shapefile can be created.

3
The Process

• Make a street (line) theme matchable
• Match a list of addresses
• Handling unmatched addresses

4
Making a Theme Matchable

• Address Style
• US Streets
• US Streets with Zones
• 5 Digit Zip
• Single Field
• Others

5
Attribute Fields

• US Streets
• LeftFrom
• LeftTo
• RightFrom
• RightTo
• StreetName
• Predir/Sufdir
• StreetType

6
Specifying an Address Style

• Theme Properties

Required for this type
Attribute Field Names
7
A Matchable Theme

• If you dont want to use a field not required be
  sure and set the attribute field to None
• When you select OK in the Theme Properties dialog
  ArcView builds a couple of geocoding index files
• .ixs
• .mxs

8
Matching a List of Addresses

• You need a table file
• One field must contain addresses

9
Matching Addresses
10
The Score

• Each component is scored according to how well it
  matches
• Weight (name is most important)
• Cotonwood where Cottonwood is expected would
  score less than perfect
• Weighted scores above 75 are considered acceptable

11
Interactive Rematch

• Records with less than 60 you can examine and see
  why the score is low
• You can choose to have a low score match accepted

12
Geocoding Preferences