GIS 1 Geocoding. GIS 2 Geocoding Address Geocoding - Process of creating geometric representations...

GIS 1

Geocoding

GIS 2

Geocoding

•Address Geocoding-Process of creating geometric representations for locations (such as point features) from descriptions of locations (such as addresses)

•Displays tabular data containing addresses as points on a map

•Finds locations on a map easily

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 3

Geocoding Examples

M. Helper 9-16-03 GEO327G/386G, UT Austin 3

• Pittsburgh Technology Council maps technology businesses by streets to see technology rich areas

• Emergency dispatch operators geocode to enter an address, determine who should respond

• Allegheny County maps personal care and nursing homes and compares to elderly population by mcds

• General Nutrition Centers maps store locations and compares to Rite-Aid store locations

• Others?

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 4

Address Matching

GIS 5

Address Matching

• Address matching is a process that compares two addresses to determine whether or not they are the same.

• Looks for certain standards and makes a decision about whether addresses match.

• Incorrect, incomplete, or ambiguous address information will reduce the matching confidence.

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 6

What do you match? Tabular data

•Text•Databases

to

Geographic maps•TIGER Streets•ZIP Codes

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 7

TIGER Files

Geographic elements used to address match•Lines -streets, railroads, rivers

•Areas-zip codes, census blocks, tracts, MCD/CCDs, places, counties, etc.

•Points-landmarks such as churchs, schools, and other cultural features represented in TIGER as points

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 8

TIGER Street Example

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 9

Linear (Street) Address Matching

GIS 10

Linear Address Matching (Streets)

Urban street maps -four street address numbers ranging from low to high for each side of a street segment.

Left_from Left_to Right_from Right_to Street_name Type 101 199 100 198 OAK ST

0105

0107

100 198

101 199

Oak St.

(80.731, 40.025) (80.729, 40.025)

GIS 11

Address Matching Major Steps

1437

402

855

123 Oak St

333 Pine Av

18 Bay Dr

A

A

B

StoreID Address Class

Store.dbf

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 12

Address Matching Major Steps

1437

402

855

123 Oak St

333 Pine Av

18 Bay Dr

A

A

B

StoreID Address Class

Store.dbf

98

99

198

199

Oak

Oak

Oak

Oak

R

L

R

L

O

E

E

O

To Street Side ParityFrom

1

100

101

2

Type

St

St

St

St

Attributes of StreetsStreet_

5950

5950

6011

6011

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 13

Address Matching Major Steps

1437

402

855

123 Oak St

333 Pine Av

18 Bay Dr

A

A

B

StoreID Address Class

Store.dbf

98

99

198

199

Oak

Oak

Oak

Oak

R

L

R

L

O

E

E

O

To Street Side ParityFrom

1

100

101

2

Type

St

St

St

St

Attributes of StreetsStreet_

5950

5950

6011

6011

5950 6011Oak St

Pin

e A

v

100

101

198

199123

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 14

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 15

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 16

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 17

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, suffix 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 18

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, suffix 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, prefix 123 W Oak ST, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 19

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, suffix 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, prefix 123 W Oak ST, Apt. 2, Pittsburgh, PA 15213

Unit Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 20

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, suffix 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, prefix 123 W Oak ST, Apt. 2, Pittsburgh, PA 15213

Unit Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Zone, city 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Zone, zip code 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 21

Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, suffix 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Direction, prefix 123 W Oak ST, Apt. 2, Pittsburgh, PA 15213

Unit Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Zone, city 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Zone, zip code 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213

Items for Single Number Street Address: Address Unit City Zip Code

123 Oak ST W Apt. 2 Pittsburgh 15213

Address Components

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 22

Street Address Matching Problems and Solutions

GIS 23

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 24

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Data Entry Errors•Fidth Avenue

•Sawmill Run

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 25

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Data Entry Errors•Fidth Avenue

•Sawmill RunPlace Names•CMU, PNC Park, Station Square

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 26

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Data Entry Errors•Fidth Avenue

•Sawmill Run

Place Names•CMU, PNC Park, Station Square

Intersections•5th AV and Craig ST

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 27

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Data Entry Errors•Fidth Avenue•Sawmill Run

Place Names•CMU, PNC Park, Station Square

Intersections•5th AV and Craig STZones•100 Main ST 15101, 100 Main ST 16202

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 28

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Data Entry Errors•Fidth Avenue•Sawmill Run

Place Names•CMU, PNC Park, Station Square

Intersections•5th AV and Craig STZones•100 Main ST 15101, 100 Main ST 16202Post Office Boxes•P.O. Box 125

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 29

Possible Problems: Variations in Street Names

•Fifth Avenue, Fifth Ave., 5th AV•Saw Mill Run, Route 51

Data Entry Errors•Fidth Avenue•Sawmill Run

Place Names•CMU, PNC Park, Station Square

Intersections•5th AV and Craig STZones•100 Main ST 15101, 100 Main ST 16202Post Office Boxes•P.O. Box 125•Missing Street (TIGER) information

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 30

Solution: Correct Intersections

Format:

Forbes AV & Craig ST

Grant ST & 5th AV

Default DelimitersArcView: &ARC/INFO: /

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 31

Solution: Use Standard Directions

E E EA E EAS E EAST E EX EX EXT EX EXTENDED EX EXTENSION EX N N NO N NORTE N NORTH N NE NE NORTHEAST NE

NW NW

NORTHWEST NW

S S

SO S

SOUTH S

SE SE

SOUTHEAST SE

SW SW

SOUTHWEST SW

W W

WE W

WEST W

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 32

Solution: Use Standard Street Type Abbreviations CR CR

Crescent CR

CRSG CRSG

CSWY CSWY

DR DR

Drive DR

DRV DR

EXP EXWY

Expressway EXWY

EXPWYEXWY

Freeway FRWY

FRWY FRWY

FWY FRWY Highway HWY HWY HWY HY HWY LA LA Lane LA LN LA Loop Loop Motorway MTWY MTWY MTWY Parkway PKWY PKWY PKWY etc.

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 33

Solution:Alias Table

DBF Table (Name of Your Choice):

Alias Address CMU 5000 Forbes Av

Carnegie Mellon 5000 Forbes AV

Carnegie Mellon Univ 5000 Forbes AV

Carnegie Mellon University 5000 Forbes AV

Etc.

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 34

Improving Address Matching

•Integrate User Data Entry and Address Matching

•Purchase or Build High Quality Maps (Field Verification)

•Correct and Maintain Maps (Lab)•Assign House Numbers in Rural Areas

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 35

Polygon Address Matching

GIS 36

TIGER Files: Polygon Topology

Zip Code

American Indian Reservation

Alaska Nature Village Statistical Area

Tribal Designated Statistical Area

Tribal Jurisdiction Statistical Area

Alaska Nature Regional Corp.

FIPS State Code

FIPS County Code

MCD

Place

Census Tract/Block Numbering Area

Tabulation Block

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 37

TIGER:Polygons - Zipcodes/Parcels

Polygon features can be identified by their parcel numbers, postal zip, or zip+4 codes

•Parcel_Number (1046)

•ZIP (15218)•ZIP + 4 (15218-1234)

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 38

Polygon Address Matching (Zip Codes)

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 39

Patient Location by County

Copyright – Kristen S. Kurland, Carnegie Mellon University

GIS 40

Geocoding in ArcGIS

GIS 41

Create address locator

ArcCatalog

GIS 42

Choose address locator style

Skeleton of the address locator

Based on data tables and reference layer

GIS 43

Choose reference layer

Streets, ZIP codes

GIS 44

Address locator properties

GIS 45

Geocode in ArcMap

1. Add tabular data and streets layer

2. Add address locator

3. Geocode addresses

4. View geocoding results

5. Interactively rematch addresses

GIS 46

Address rematching

Investigate unmatched addresses•Generally requires expertise with knowledge of local streets

•Compare street name in the attributes of streets table and address table

GIS 47

Prepare log file

Log file includes reasons why addresses did not geocode

Useful for future work on cleaning addresses or repairing street maps

Incorrect address Possible reason/solution

490 Penn Avenue Missing ZIP code

111 Hawksworth Spelled incorrectly

900 Smallman Street TIGER street missing

900 Lib Ave Spelled incorrectly