1. Population and Housing Estimates for Census Blocks: The San Diego Experience Jeff Tayman San Diego Association of Governments

2. Presentation Topics Describe the San Diego Estimation System Study Comparing Two Sources of Address Data Issues in Doing Block-Level Estimates

3. Geographic Boundary System Master Geographic Areas (MGRA) Based on census blocks Some blocks are split Approximately 30,000 areas

4. Information Easily Accessible Standard Geographies Cities Zip Code Areas Or Non-Standard Radius from a Point Buffer Area User Defined Area

5. Methodology and Data Housing Unit Method Top Down Approach Official State Estimates Local Housing Unit Permit Data Assessors Parcel Data Vacancy Rates, PPH and GQ Pop

6. Geographic Sequence Jurisdiction EstimatesState Estimates Census Tract EstimatesLocal Housing Permits MGRA EstimatesAssessors Parcels

7. MGRA Estimates Address-Level Data Sets –Assessors Parcel File –Group Quarters Facilities Street Centerline and Address File GIS Admatch Procedure

8. Admatch- Assign Activities to Spatial Locations 2142 Diamond St. 1832 Grand Ave. 1532 Missouri Ave. 1190 Emerald St.

9. Evaluation of Two Address- Level Administrative Records Utility Meter Hook-ups Assessors Parcel Data Test Period 1990-1996 Jurisdictions and Census Tracts Use Local Permits as Standard

10. Error in 1996 Housing Stock Jurisdictions

11. Error in 1996 Housing Stock Census Tracts

12. Error of the 1990-96 Change Jurisdictions

13. Error of the 1990-96 Change Census Tracts

14. Utility Hook-ups Need 1-to-1 Match with New Units Replacement Meters a Problem Master Meters Need Unit Count No Accounting for Lost Units Not Easy to Get –Deal with multiple companies –Deregulation

15. Assessors Parcels Units at Address for Apartments and Condominiums an Issue Year Built Not Precise Determining Lost Units Difficult Less Problems with Multiple Agencies Serving a County Relatively Easy to Get –Private Vendors –$1,300 per year

16. Maintaining an Up-to-Date GIS Address Files –Misspellings, Abbreviations, Omissions –PO Boxes Street Centerline Files –Missing streets and address ranges –Keeping it current Registration

17. Poorly Registered Street and Boundary Files Block 101Block 102 3rd Avenue 1510 3rd Ave 3rd Avenue

18. Some Issues in Producing Very Small Area Estimates Data Management Temporal Consistency Boundary Changes Vacancy Rates and PPH Controlling Accuracy

19. Population and Housing Estimates for Census Blocks: The San Diego Experience Jeff Tayman San Diego Association of Governments