Fundamentals of crime mapping Geocoding

2. Geocoding is the process of getting tabular

data from a data source, comparing it to a
geographic layer (like a shapefile) and then
displaying the address matches in ArcGIS, at
the location where the match was made

3. Create a table of addresses you want to match…
Access database
Excel Spreadsheet
Comma Delimited File

4. Obtain a GIS Layer which has address information and fields to match to!
Geodatabase
File Geodatabase
ArcGIS Shapefile

5. Create an address locator in Arc Catalog…
Right click on a folder and
choose NewAddress
Locator, or
use the ArcToolbox

6. Open ArcGIS and add the table…
Attribute Table to be geocoded with an address
Right click on table, and choose geocode addresses

7. Add the Address Locator…

8. Set up the Address Locator
and geocoding options…
Address table
Is the table with addresses to be
geocoded
Street or Intersection and
Zone
The fields in the table to try and
match
Output Shapefile or Feature
Class
Where are you saving the new
geocoded file to?
Geocoding Options
How accurate do you want the
point to be?

9. Geocoding Options…
Spelling Sensitivity
Do you want Indian Bend and
Indian School to match?
Minimum candidate score
What score does a recod match
need to be to be considered a
possible match?
Minimum match score
At what score do we want to
match or not match and place the
point at that location?
Side offset
How far away from the centerline
do you want the point to be drawn?
End Offset
How far away from an
intersection do you want the point
drawn?

10. OffSet Distances
Businesses
Average 175 feet
Residential
Average 55 feet
Overall Average
Average 101 feet
From center of roadway to
front door

11. Geocode those puppies…

12. Allows you to see why
Match interactively as addresses are not matching
needed… and correct the problem
Time Consuming – one at a
time
With this table there was no ZONE field

13. Map the geocoded data and understand it’s limitations…
Data
quality can
be a huge
issue
with some
data
depending
on the scale
at which
the data is
displayed

14. WHOAAA
THAR!!!!
It’s time for a
Break!