Household Surveys: American Community Survey & American Housing Survey

1. Household Surveys:American Community Survey&American Housing Survey Warren A. BrownFebruary 8, 2007

2. Purpose Target Population Sampling Frame Data Collection Non-Response Missing Data Weighting Sampling Error Access to Reports …to Aggregate Data …to Microdata Research Questions Outline

3. ACS: Purpose • Key Component for Re-Engineered Census • Replacing the Decennial Census “Long-Form” • Continuous measurement rather than snapshot • Meet federal legislative and program needs • Other stakeholders in state and local government and private sectors • Provide annual data on demographic, social, economic and housing characteristics. • Proportions rather than counts

4. ACS: Target Population • Current residence not “Usual Residence” • “two-month rule” • Household population in 2005 • Total (HH + GQ) in 2006 and …. • GQ residency is “de facto”

5. ACS: Sampling Frame • Master Address File (MAF) • Official inventory of known living quarters • Linked to TIGER • Housing Units • Based on Census 2000 MAF and updates from the USPS’ Delivery Sequence File • Group Quarters • … and updates from the administrative records and the FSCPE • Excluded from ACS are domestic violence shelters, soup kitchens, commercial maritime vessels,…

6. ACS: Design of the Sample • Annual Sample Size of 3 million addresses • Series of Monthly Samples of 250,000 addresses • HU sample in each of the 3,141 Counties • Areas with smaller populations sampled at higher rates than those with larger populations • HU Address sampling rate set by Block based on entity (municipality, school district, tract) • Final sampling rate varies between 1.6% and 10% • No HU address can be sampled more than once in 5 years

7. ACS: Sample Design cntd • GQ facilities sample for each state • Two stratum • Small (15 or fewer residents) • Large ( more than 15 residents) • Small • Data collected on all residents • Facility eligible once in 5 years • Large • Groups of ten residents sub-sampled • Number of groups determined by size of facility • Facility eligible every year

8. ACS: Data Collection • HU addresses by three modes • Mailout of paper questionnaire in 1st month • Telephone (CATI) non-response follow-up in 2nd month • Personal visit (CAPI) non-response follow-up in 3rd month to a sub-sample • GQ • Personal visit within 6 weeks of sample selection

9. Data Collection Timetable

10. ACS: Questionnaire • Content designed to meet the needs of federal government agencies • 25 housing and 42 population questions (6 basic and 36 detailed) • Household Respondent provides responses for all other residents of the household • Householder or Reference Person is “Person 1”

11. ACS: Response Rates • Participation is mandatory • Sample addresses eligible for interviewing: • 51% Mail response • 9% CATI non-response follow-up • 38% CAPI non-response follow-up • 2% Non-interview

12. ACS: Missing Data Item non-response or failed edit check • FEFU – failed-edit follow-up • More than 5 household members • Critical questions not answered • 33% of mail return questionnaires in 2005 • Imputation • Assignment used other data on respondent • Allocation – hot deck procedure • Flags variables

13. ACS: Weighting • Person and Housing Unit weights • Three stages • Probability of selection (initial sampling rate) • Adjust for non-response • Control to Intercensal Population Estimates • Sum the weights • Person weights for person characteristics • HU weights for family, household or housing unit characteristics • Householders = Households ???

14. ACS: Weighty Issues ACS 2005 for United States • 288,378,137 Persons in Households • 111,090,617 Households • 114,763,475 Householders • Average Household Size • 2.60 based on Households • 2.51 based on Householders

15. ACS: Sampling Error • Publishing margins of error in tables • More sample less error • 1, 3, and 5 year estimates and associated sampling error • Sampling error for small area data

16. Access to Reports/Tables/Data • ACS section of Census.gov • American FactFinder • ACS FTP Site • ACS Data Tables • ACS Public Use Microdata

17. www.census.gov/acs/www/

18. American Community SurveyProgram Schedule • ACS Demonstration Period: 1996-2004 • 2000-2004 data products: Summer, 2005 • ACS full implementation began January 2005 • First full implementation data products: Summer, 2006 • Annually updated data products every year thereafter

19. Full Implementation • 3 million addresses every year throughout the U.S. and in Puerto Rico • Provide annual profiles for communities of 65,000 or more • Provide 3- to 5-year cumulations for communities of less than 65,000 population

21. ACS Sample Design

22. ACS “Long Form” Data by Geography

23. ACS vs Traditional Census

24. ACS: Access to Aggregate Data • Tabular data on American FactFinder • Summary Files similar to SF3 being tested

25. ACS: Access to Microdata • ACS 2005 PUMS on • American FactFinder • Data Ferrett • Tabulated Estimates for User Verification • ACS PUMS is a sub-sample representing 1% of total housing units

29. ACS: Research Questions