Geocoding GIS 1 Geocoding Address Geocoding Process of

Geocoding GIS 1

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 2

Geocoding Examples • 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 3

Address Matching GIS 4

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 5

What do you match? Tabular data • Text • Databases to Geographic maps • TIGER Streets • ZIP Codes Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 6

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 7

TIGER Street Example Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 8

Linear (Street) Address Matching GIS 9

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 101 Left_to 199 Right_from 100 0105 0107 Right_to 198 100 101 (80. 731, 40. 025) Street_name OAK Oak St. Type ST 198 199 (80. 729, 40. 025) GIS 10

Address Matching Major Steps Store. dbf Store. ID Address Class 1437 123 Oak St A 402 333 Pine Av A 855 18 Bay Dr B Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 11

Address Matching Major Steps Store. dbf Store. ID Address Class 1437 123 Oak St A 402 333 Pine Av A 855 18 Bay Dr B Attributes of Streets Type Side Parity Street_ From To Street 2 98 Oak St R E 5950 1 99 Oak St L O 5950 100 198 Oak St R E 6011 101 199 Oak St L O 6011 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 12

Address Matching Major Steps Store. dbf Address Class 1437 123 Oak St A 402 333 Pine Av A 855 18 Bay Dr Oak St 100 5950 Pine Av Store. ID B 6011 101 198 199 123 Attributes of Streets Type Side Parity Street_ From To Street 2 98 Oak St R E 5950 1 99 Oak St L O 5950 100 198 Oak St R E 6011 101 199 Oak St L O 6011 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 13

Address Components Number 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 14

Address Components Number Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 15

Address Components Number Street Name 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213 Street Type 123 Oak ST W, Apt. 2, Pittsburgh, PA 15213 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 16

Address Components Number 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 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 17

Address Components Number 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 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 18

Address Components Number 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 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 19

Address Components Number 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 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 20

Address Components Number 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 123 Oak ST W Apt. 2 City Pittsburgh Zip Code 15213 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 21

Street Address Matching Problems and Solutions GIS 22

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 23

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Data Entry Errors • Fidth Avenue • Sawmill Run Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 24

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Data Entry Errors • Fidth Avenue • Sawmill Run Place Names • CMU, PNC Park, Station Square Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 25

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Data Entry Errors • Fidth Avenue • Sawmill Run Place Names • CMU, PNC Park, Station Square Intersections • 5 th AV and Craig ST Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 26

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Data Entry Errors • Fidth Avenue • Sawmill Run Place Names • CMU, PNC Park, Station Square Intersections • 5 th AV and Craig ST Zones • 100 Main ST 15101, 100 Main ST 16202 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 27

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Data Entry Errors • Fidth Avenue • Sawmill Run Place Names • CMU, PNC Park, Station Square Intersections • 5 th AV and Craig ST Zones • 100 Main ST 15101, 100 Main ST 16202 Post Office Boxes • P. O. Box 125 Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 28

Possible Problems: Variations in Street Names • Fifth Avenue, Fifth Ave. , 5 th AV • Saw Mill Run, Route 51 Data Entry Errors • Fidth Avenue • Sawmill Run Place Names • CMU, PNC Park, Station Square Intersections • 5 th AV and Craig ST Zones • 100 Main ST 15101, 100 Main ST 16202 Post Office Boxes • P. O. Box 125 • Missing Street (TIGER) information Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 29

Solution: Correct Intersections Format: Forbes AV & Craig ST Grant ST & 5 th AV Default Delimiters Arc. View: & ARC/INFO: / Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 30

Solution: Use Standard Directions E EA EAST EX EXTENDED EXTENSION N NO NORTE NORTH NE NORTHEAST E E EX EX N N NE NE NW NORTHWEST S SO SOUTH SE SOUTHEAST SW SOUTHWEST W WE WEST NW NW S SE SE SW SW W Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 31

Solution: Use Standard Street Type Abbreviations CR Crescent CRSG CSWY DR Drive DRV EXP Expressway EXPWY Freeway FRWY CR CR CRSG CSWY DR DR DR EXWY FRWY FWY Highway HWY HY LA Lane LN Loop Motorway MTWY Parkway PKWY etc. FRWY HWY HWY LA LA LA Loop MTWY PKWY Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 32

Solution: Alias Table DBF Table (Name of Your Choice): Alias Address CMU Carnegie Mellon University Etc. 5000 Forbes Av 5000 Forbes AV Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 33

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 34

Polygon Address Matching GIS 35

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 36

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 37

Polygon Address Matching (Zip Codes) Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 38

Patient Location by County Copyright – Kristen S. Kurland, Carnegie Mellon University GIS 39

Geocoding in Arc. GIS 40

Create address locator Arc. Catalog GIS 41

Choose address locator style Skeleton of the address locator Based on data tables and reference layer GIS 42

Choose reference layer Streets, ZIP codes GIS 43

Address locator properties GIS 44

Geocode in Arc. Map 1. Add tabular data and streets layer 2. Add address locator 3. Geocode addresses 4. View geocoding results 5. Interactively rematch addresses GIS 45

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 46

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 GIS 47