1. Session: Parcel/Address Data Maintenance How Addresses Are Used in GIS Presenter: Wade Kloos, ESRI Date: Thursday, October 4, 2001

2. October 2001 Tidemark User's Conference2 How Addresses Are Used In GIS Addresses can be used to join or relate GIS data to other agency databases (police, sales-tax and other non-APN based datasets) Addresses are valuable attributes for managing GIS features (parcels, businesses, utilities,etc.)

3. October 2001 Tidemark User's Conference3 The Search for Map Position GEOCODING also called ADDRESS MATCHING Depicting the relationship of a record’s address to a mapped street feature.

4. October 2001 Tidemark User's Conference4 GeoCoding – How It Works Interpolating Process Compares a record’s address attribute to the address range of a mapped feature – a road. 100 Main St. 200 101 199 170 Main St.

5. October 2001 Tidemark User's Conference5

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7. 7 123 Main Street 100-200 Main St. 95 123 Maine St.100-200 Main St. 80 123 Mane Rd.100-200 Main St. 50/DNP 99 Main St.100-200 Main St. DNP Scoring GeoCoded Matches Example: Record Range Score The GeoCoding process assigns a match score to each address – if the match score is over a certain threshold, the program will map the record.

8. October 2001 Tidemark User's Conference8 GeoCoding – Not an Exact Science Placement can be affected by: Inconsistencies of data entry process Subtleties of the GeoCoding scoring methods The interpretive process itself Land use patterns However, GeoCoding is useful when address data is less than perfect

9. October 2001 Tidemark User's Conference9 Another Address Location Option ISSUES: Not a Batch Process – unless custom scripts are built No tolerance for dissimilar addresses – no interpolation Once matched, placement is as accurate as features are mapped Direct queries against GIS feature databases - Polygons and Points

10. October 2001 Tidemark User's Conference10 Based on parcel polygon attributes

11. October 2001 Tidemark User's Conference11 Based on point feature attributes

12. October 2001 Tidemark User's Conference12 Database Conventions To maximize usefulness of address information, a database should have the several data fields, including but not limited to: Street Number (numerical/alphanumeric) Street Name Street Name Prefix Street Name Suffix Unit Number (residential apt. or condo) Suite Number (businesses) Address – combo of number, street, suffix, etc. City Zip Zip + 2,4

13. October 2001 Tidemark User's Conference13 Database Standards Standardization of addressing syntax is critical for consistent search results and integration with other application databases. Develop and adopt a master address database - from USPS or existing city databases – both of which requires QC by staff Every field needs to be QC

14. October 2001 Tidemark User's Conference14 Database Standards 1 st vs. First E. Ball vs. East Ball Avenida del Caballo vs. Ave. Del Caballo King Court vs. King Ct

15. October 2001 Tidemark User's Conference15 Using GIS to QC Address Data

16. October 2001 Tidemark User's Conference16 Using GIS to QC Address Data