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Documentation:
ACS 2008 (1-Year Estimates)
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Publisher:
U.S. Census Bureau
Survey:
ACS 2008 (1-Year Estimates)
Documentation
ACS 2008 (1-Year Estimates)
American Community Survey Office
U.S. Census Bureau
ACS 2008-1yr Summary File: Technical Documentation
Chapter 1. Abstract
1.1. Citation
1.2. Special Notes
1.3. Notes on Updates to the Technical Document Since 2008
1.3.1. Updated Chapters
1.3.2. Updated Appendices
1.4. Type of File
1.5. Subject Content
1.6. Geographic Content
1.6.1. State Files
1.6.2. National Files
1.7. Document Overview
1.8. User Updates
Chapter 2. How to Use the ACS Summary File
2.1. Introduction
2.2. Data Format
2.3. File Naming Conventions
2.4. Reading the Geographic Header Record
2.5. Geographic Hierarchy Primer
2.6. Worked Example
2.7. Data Structure and Segmentation
Chapter 3. Subject Locator
Chapter 4. Summary Level Sequence Chart
4.7. Table Name Changes - ACS 5yr
4.8. Table Name Changes - ACS 1yr
Chapter 5. List of Detailed Tables
Chapter 6. Accuracy of the Data
6.1. 2008 ACS Accuracy of the Data (US)
6.1.1. Introduction
6.1.2. Data Collection
6.1.3. Sampling Frame
6.2. 2008 ACS Accuracy of the Data (Puerto Rico)
6.2.1. Introduction
6.2.2. Data Collection
6.2.3. Sampling Frame
6.2.4. Sample Design
6.2.5. Weighting Methodology
6.2.6. Confidentiality of the Data
6.2.7. Errors in the Data
6.2.8. Measures of Sampling Error
6.2.9. Calculation of Standard Errors
6.2.10. Examples of Standard Error Calculations
6.2.11. Control of Nonsampling Error
Chapter 7. User Updates
Appendix A. ACS Geographic Terms and Concepts
Introduction-Geographic Presentation of Data
Hierarchical Presentation
Inventory Presentation
American Indian/Alaska Native Area/Hawaiian Home Land (AIANA/HHL) Entities
American Indian Area, Alaska Native Area, Hawaiian Home Land
Alaska Native Regional Corporation (ANRC)
Alaska Native Village Statistical Area (ANVSA)
American Indian Reservation
American Indian Off-Reservation Trust Land
American Indian Tribal Subdivision
Hawaiian Home Land (HHL)
Oklahoma Tribal Statistical Area (OTSA)
State Designated American Indian Statistical Area (SDAISA)
Tribal Designated Statistical Area (TDSA)
Area Measurement
Block Group (BG)
Boundary Changes
Census Block
Census Division
Census Region
Census Tract
Congressional District (CD)
County (or Statistically Equivalent Entity)
County Subdivision
Census County Division (CCD)
Census Subarea
Minor Civil Division (MCD)
Unorganized Territory
Geographic Code
Census Code
Federal Information Processing Standards (FIPS) Code
United States Postal Service (USPS) Code
Internal Point
Island Areas of the United States
Metropolitan Area (MA)
Central City
Consolidated and Primary Metropolitan Statistical Area (CMSA and PMSA)
Metropolitan Statistical Area (MSA)
Metropolitan Area Title and Code
New England County Metropolitan Area (NECMA)
Place
Census Designated Place (CDP)
Consolidated City
Incorporated Place
Population or Housing Unit Density
Public Use Microdata Area (PUMA)
Puerto Rico
Municipio
Barrio, Barrio-Pueblo, and Subbarrio
Zona Urbana and Comunidad
School District
State (or Statistically Equivalent Entity)
State Legislative District (SLD)
TIGER® Database
Traffic Analysis Zone (TAZ)
Tribal Block Group
Tribal Census Tract
United States
Urban and Rural
1
Urban Cluster (UC)
Urbanized Area (UA)
Extended Place
Urban Growth Area (UGA)
Voting District (VTD)
ZIP Code® Tabulation Area (ZCTA)
Combined New England City and Town Area (CNECTA)
Combined Statistical Area (CSA)
Core Based Statistical Area (CBSA)
Metropolitan Division
Metropolitan Statistical Area/Micropolitan Statistical Area
New England City and Town Area (NECTA)
New England City and Town Area (NECTA) Division
State Designated Tribal Statistical Area (SDTSA)
Appendix B. Subject Definitions
Living Quarters
Housing Unit
Group Quarters
Housing Variables
General Information
Acreage (Cuerda)
Agricultural Sales
Bedrooms
Business on Property
Condominium Status and Fee
Contract Rent
Food Stamp Benefits
Gross Rent
Gross Rent as a Percentage of Household Income
Homeowner Vacancy Rate
House Heating Fuel
Household Size
Housing Units
Insurance for Fire, Hazard, and Flood
Kitchen Facilities
Meals Included in Rent
Mobile Home Costs
Monthly Housing Costs
Monthly Housing Costs as a Percentage of Household Income
Mortgage Payment
Mortgage Status
Occupants Per Room
Occupied Housing Units
Owner-Occupied Units
Plumbing Facilities
Population in Occupied Housing Units
Poverty Status of Households
Real Estate Taxes
Rent Asked
Rental Vacancy Rate
Renter-Occupied Housing Units
Rooms
Second or Junior Mortgage Payments or Home Equity Loan
Selected Conditions
Selected Monthly Owner Costs
Selected Monthly Owner Costs as a Percentage of Household Income
Specified Owner-Occupied Units
Specified Renter-Occupied Units
Telephone Service Available
Tenure
Units in Structure
Utilities
Vacancy Status
Vacant-Current Residence Elsewhere
Vacant Housing Units
Value
Vehicles Available
Year Householder Moved into Unit
Year Structure Built
Population Variables
General Information
Ability to Speak English
Age
Ancestry
Children Ever Born
Citizenship Status (U.S. Citizenship Status)
Class of Worker
Disability Status
Educational Attainment
Employment Status
Families
Fertility
Foreign-Born Population
Foster Children
Grade in Which Enrolled
Grandparents as Caregivers
Group Quarters (GQ)
Health Insurance Coverage
Hispanic or Latino Origin
Household
Household Type and Relationship
Household Size
Householder
Immigrants
Income in the Past 12 Months
Industry, Occupation, and Class of Worker
Journey to Work
Labor Force Status
Language Spoken at Home and Ability to Speak English
Marital Status/Marital History
Means of Transportation to Work
Migration
Native Population
Nativity
Nativity of Parent
Occupation
Own Children
Period of Military Service
Persons in Family
Persons in Household
Place of Birth
Place of Work
Poverty Status in the Past 12 Months
Private Vehicle Occupancy
Race
Reference Week
Relatives and Nonrelatives
Residence 1 Year Ago
School Enrollment and Type of School
Sex
Social Security Income
Subfamily
Time Leaving Home to Go to Work
Travel Time to Work
Type of School
Usual Hours Worked in the Past 12 Months
Veteran Status
Weeks Worked in the Past 12 Months
Work Experience
Work Status in the Past 12 Months
Year of Entry
Quality Measures
General Information
Sample Size
Coverage Rates
Response Rates
Imputation Rates
Derived Measures
Aggregate
Average
Gini Index
Interpolation
Mean
Aggregate
Rounding for selected aggregates
Special rounding rules for aggregates
Aggregates Subject to Rounding:
Median
Percentage
Quartile
Quintile
Rate
Ratio
Appendix C. Data Collection and Processing Procedures
C.1. Self-enumeration through mail-out/mail-back methodology
C.2. Computer Assisted Telephone Interviewing (CATI)
C.3. Computer Assisted Personal Interviewing (CAPI)
Appendix D. Questionnaire
The American Community Survey 2008
2008 ACS Questionnaire - English
2008 ACS Group Quarters Questionnaire (English and Spanish)
The Puerto Rican Community Survey 2008
2008 PRCS Questionnaire- English
2008 PRCS Group Quarters Questionnaire (English and Spanish)
Appendix E. Data Products and User Assistance
Appendix F. Maps
Appendix G. Code Lists
2008 American Community Survey/Puerto Rico Community Survey
Group Quarters
Correctional Facilities for Adults
Juvenile Facilities
Nursing Facilities/Skilled Nursing Facilities
Other Health Care Facilities
College/University Student Housing
Military Group Quarters
Other Noninstitutional Facilities
Appendix H. Examples of Standard Error Calculations
Appendix I. Sample SAS Programs
Appendix J. User Notes
Social Explorer; U.S. Census Bureau; American Community Survey 2008 Summary File: Technical Documentation.
Design and Methodology: American Community Survey
Acknowledgments
Foreword
The American Community Survey-A Revolution in Data Collection
The Beginning
Annual results will be available for all areas by 2010
The 2008 release of the ACS Design and Methodology Report
Success of the Program
Chapter 1. Introduction
Chapter 2. Program History
Overview
Design Origins and Early Proposals
Development
Demonstration
Full Implementation
Stakeholders and Contributors
References
Chapter 3. Frame Development
Overview
Master Address File Content
Master Address File Development and Updating for the Uinted States Housing Unit Iinventory
MAF Development in the United States
MAF Improvement Activities and Operations
Delivery Sequence File
MAFGOR
Address Updates From ACS Nonresponse Follow-Up
DAAL
CAUS
Master Address File Development and Updating for Puerto Rico
MAF Development in Puerto Rico
MAF Improvement Activities and Operations in Puerto Rico
Master Address File Development and Updating for Special Places and Group Quarters in the United States and Puerto Rico
MAF Development for Special Places and GQs
MAF Improvement Activities and Operations for Special Places and GQs
American Community Survey Extracts from the Master Address File
References
Chapter 4. Sample Design and Selection
Overview
Housing Unit Sample Selection
First-Phase Sample
Main and Supplemental Sampling
Determining the Sampling Rates
First-Stage Sample: Random Assignment of Addresses to a Specific Year
Second-Stage Sampling: Selection of Addresses
Sample Month Assignment for Address Samples
Second-phase Sampling for CAPI Follow-up
Group Quarters Sample Selection
Small Group Quarters Stratum Sample
First Phase of Small GQ Sampling-Stage One: Random Assignment of GQ Facilities to Subframes
First Phase of Small GQ Sampling Stage Two: Selection of Facilities
Second Stage of Small GQ Sampling: Selection of Persons Within Selected Facilities
Large Group Quarters Stratum Sample
First Phase of Large GQ Sampling: Selection of Groups of Ten (and Associated Facilities)
Second Phase of Large GQ Sampling: Selection of Persons Within Facilities
Sample Month Assignment for Small and Large Group Quarter Samples
Remote Alaska Sample
References
Chapter 5. Content Development Process
Overview
History of Content Development
2003-2007 Content
ACS Content
Puerto Rico Community Survey (PRCS) Content
Content Policy and Content Change Process
Content Change Factors
Content Change Requirements
2006 Content Test
References
Chapter 6. Survey Rules, Concepts, and Definitions
Overview
Interview Rules
Residence Rules
Housing Units
Group Quarters
Reference Period
Structure of the Housing Unit Questionnaire
Address, Housing Unit Status, and Household Information
Basic Demographic Information
Detailed Housing Information
Detailed Population Information
Structure of the Group Quarters Questionnaires
Chapter 7. Data Collection and Capture for Housing Units
Overview
Mail Phase
Mailout
Check-In
Telephone Questionnaire Assistance (TQA)
Data Capture
Failed-Edit Follow-Up
Telephone Phase
Personal Visit Phase
Data Collection in Remote Alaska
References
Chapter 8. Data Collection and Capture for Group Quarters
Overview
Group Quarters (Facility)-Level Phase
Previsit Mailings
GQ Introductory Letter
GQ Frequently Asked Questions (FAQ) Brochure
GQ State and Local Correctional Facilities Letter
Initial Contact With GQ Facility
Visiting the GQ Facility
Person-Level Phase
Preparation
Person-Level Survey Materials
Completing the GQ Questionnaire
Questionnaire Review
Check-In and Data Capture
Check-In
Data Capture
Special Procedures
Biannual Data Collection in Remote Alaska
Annual Data Collection Restrictions in Correctional and Military Facilities
Survey Period and Security Restrictions in Federal Correctional Facilities
Chapter 9. Language Assistance Program
Overview
Background
Guidelines
Mail Data Collection
Telephone and Personal Visit Follow-Up
Group Quarters
Research and Evaluation
References
Chapter 10. Data Preparation and Processing for Housing Units and Group Quarters
Overview
Data Preparation
Creation and Preparation of Data Capture Files
Daily Data Processing
Monthly Data Processing
Coding
Backcoding
Industry and Occupation Coding
Geocoding
Preparation for Creating Select Files and Edit Input Files
Response Type and Number of People in the HU
Determining if a Return Is Acceptable
Unduplicating Multiple Returns
Creating the Select Files and Edit Input Files
Select Files
Edit Input Files
Data Processing
Editing and Imputation
Editing
Imputation
Generating Recoded Variables
Reviewing Edit Results
Creating Input Files for Data Products
Multiyear Data Processing
References
Chapter 11. Weighting and Estimation
Overview
2007 ACS Group Quarters Person Weighting
Sampling Weight
Calculation of the GQ NonInterview Adjustment Factor
Calculation of the GQ Person Post-Stratification Factor
2007 ACS Housing Unit Weighting-Overview
2007 ACS Housing Unit Weighting-Probability of Selection
Sampling Weight
Variation in the Monthly Sample Factor
2007 ACS Housing Unit Weighting-Noninteview Adjustment
Calculation of the First Noninterview Adjustment Factor
Calculation of the Second Noninterview Adjustment Factor
Calculation of the Mode Noninterview Factor and Mode Bias Factor
2007 ACS Housing Unit Weighting-Housing Unit and Population Controls
Models for PEP estimates of housing units and population
Calculation of Housing Unit Post-Stratification Factor
Calculation of Person Weights
Calculation of Final Housing Unit Factors
Multiyear Estimation Methodology
Pooling the data
Geography
Derivation of the multiyear controls
Model-assisted estimation
Other multiyear estimation steps
References
Chapter 12. Variance Estimation
Overview
Variance Estimation for ACS Housing Unit and Person Estimates
Replicate Factors
Replicate Weights
Variance Estimates
Variance Estimation for Multiyear ACS Estimates
Margin of Error and Confidence Interval
Variance Estimation for the PUMS
References
Chapter 13. Preparation and Review of Data Products
Overview
Geography
Defining the Data Products
Description of Aggregated Data Products
Detailed Tables
Data Profiles
Narrative Profiles
Subject Tables
Ranking Products
Geographic Comparison Tables (GCTs)
Thematic Maps
Selected Population Profiles (SPPs)
Public Use Microdata Sample
Generation of Data Products
Disclosure Avoidance
Swapping
Data Release Rules
Data Review and Acceptance
Important Notes on Multiyear Estimates
Custom Data Products
Chapter 14. Data Dissemination
Overview
Schedule
Data Release Timetable
Presentation of Tables
American FactFinder
ACS Web Site
File Transfer Protocol (FTP) Site
Chapter 15. Improving Data Quality by Reducing Nonsampling Error
Overview
Coverage Error
Nonresponse Error
Unit Nonresponse
Item Nonresponse
Measurement Error
Processing Error
References
Acronyms
Glossary of Terms
100 Percent Data
Accessibility
Acceptability Index
Accuracy
Address Control File
Address Corrections from Rural Directories
Address Listing
Administrative Entities
Allocation
American Community Survey (ACS) Alert
American Community Survey Demonstration Program
American Community Survey Full Implementation
American Community Survey Test Sites
American FactFinder (AFF)
American Indian Area, Alaska Native Area, Hawaiian Homeland (AIANAHH)
Assignment
Automated Address Unduplication
Automated Clerical Review
Automated Editing
Automated Listing and Mapping Instrument (ALMI)
Automated Review Tool (ART)
Automated Review Tool II (ART II)
Base Tables
Base Weight
Be Counted Enumeration and Be Counted Questionnaire
Blaise
Block
Block Canvassing
Block Group
Boundary and Annexation Survey (BAS)
Case Management
Census 2000 Supplementary Survey (C2SS)
Census County Division (CCD)
Census Designated Place (CDP)
Census Geography
Census Information Center (CIC)
Census Sample Data
Census Tract
City-Style Address
Coding
Coefficient of Variation (CV)
Cold Deck Values
Collapsing
Community Address Updating System (CAUS)
Comparison Profile
Complete Interview
Computer-Assisted Personal Interviewing (CAPI)
Computer-Assisted Telephone Interviewing (CATI)
Confidence Interval
Confidentiality
Congressional Tool Kit
Consumer Price Index (CPI)
Control File
Controlled
Count Question Resolution (CQR)
Cross Tabulation
Current Population Survey (CPS)
Current Residence
Custom Tabulations
Data Capture File
Data Collection Mode
Data Profiles
De Facto Residence Rules
Delivery Sequence File (DSF)
Demographic Area Address Listing (DAAL)
Derived Products
Detailed Tables
Disclosure Avoidance (DA)
Disclosure Review Board (DRB)
Edit
Edit Management and Messaging Application (EMMA)
Estimates
Evaluation Studies
Failed Edit Follow-Up (FEFU)
Federal Agency Information Program (FAIP)
Federal Government Unit (FGU)
Federal Register Notice
Federal-State Cooperative Program for Population Estimates (FSCPE)
Field Representative (FR)
File Transfer Protocol (FTP)
Final Outcome Code
First Stage Sample
Five-Year Estimates
Functioning Governmental Unit (FGU)
General Coding
Geocoding
Geographic Summary Level
Government Printing Office (GPO)
Governmental Unit Measure of Size (GUMOS)
Group Quarters (GQ) Facilities
Group Quarters Facilities Questionnaire (GQFQ)
Group Quarters Geocoding Correction Operation
Group Quarters Listing Sheet
Group Quarters Measure of Size (GQMOS)
Hot Deck Imputation
Household
Housing Unit (HU)
Imputation
Interactive Voice Recognition (IVR)
Intercensal Estimates
Interim Codes
Interpolation
Interview Monitoring
Item Nonresponse
Iterations
Joint Economic Edit
Key-From-Image (KFI)
Key-From-Paper (KFP)
Legal Entity
List/Enumerate
Local Update of Census Addresses (LUCA)
Long Form
Lower Bound
Mailing Address
Mailout-Mailback
Main Phase Sample
Master Address File (MAF)
Master Address File Geocoding Office Resolution (MAFGOR)
Master Address File/TIGER® Reconciliation
Margin of Error (MOE)
Measure of Size (MOS)
Measurement Error
Median
Metadata
Minor Civil Division (MCD)
Multiyear Estimates
Municipio
Narrative Profile
National Processing Center (NPC)
Non-City-Style Address
Noninterview/Nonresponse
Nonresponse Error
Nonresponse Follow-Up
Nonsampling Error
Office of Management and Budget (OMB)
Operational Response Rates
Optical Mark Recognition (OMR)
Overcoverage
Period Estimates
Point-in-Time Estimates
Population Controls
Primary Sampling Unit (PSU)
Processing Error
Public Use Microdata Area (PUMA)
Public Use Microdata Sample (PUMS) Files
Public Use Microdata Sample (PUMS) Management and Messaging Application (PMMA)
Puerto Rico Community Survey (PRCS)
Quality Assurance (QA)
Quality Control (QC)
Quality Index
Quality Measures
Raking
Ranking Table
Recodes
Reference Period
Regional Office (RO)
Relevance
Remote Alaska
Residence Rules
Respondent
Respondent Errors
Response Categories
Response Errors
Rolling Sample
Sample Month
Sampling Entity
Sampling Error
Sampling Frame
Sampling Rate
Sampling Variability
Second Stage Sample
Selected Population Profiles (SPPs)
Short Form
Single-Year Estimates
Size Thresholds
Small Area Income and Poverty Estimates (SAIPE)
Special Census
Special Place (SP)
Special Sworn Status (SSS) or Special Sworn Status (SSS) Individual
Standard Error
State Data Center (SDC)
Statistical Areas
Statistical Significance
Strata
Stratum
Subsampling
Subject Tables
Successive Differences Replication (SDR)
Sufficient Partial Interview
Summary File 3 (SF 3)
Summary File 4 (SF 4)
Supplemental Sample
Survey
Survey of Income and Program Participation (SIPP)
Survey Quality
Survey Response Rates
Swapping
Systematic Errors
Tabulation Month
Tabulation Universe
Targeting
Telephone Questionnaire Assistance (TQA)
Thematic Maps
Three-Year Estimates
Timeliness
Title 13 (U.S. Code)
Topcoding
Topologically Integrated Geographic Encoding and Referencing (TIGER®) System or Database
Tract
Undeliverable-As-Addressed (UAA)
Undercoverage
Unit Nonresponse
Unmailable
Update/Leave (U/L)
Upper Bound
Urbanizacion
Urbanized Area (UA)
Usual Residence
Voluntary Methods Test
WebCATI
Web Data Server (WDS)
Weighting
Glossary of Basic Geographic and Related Terms - Census 2000
Alaska Native Regional Corporation (ANRC)
Alaska Native village (ANV)
Alaska Native village statistical area (ANVSA)
American Indian off-reservation trust land
American Indian reservation
American Indian tribal subdivision
American Indian trust land
Barrio, barrio-pueblo
Block
Block boundary
Block group (BG)
Block number
Block numbering area (BNA)
Borough
Census area
Census block
Census Bureau map
Census county division (CCD)
Census designated place (CDP)
Census division
Census geography
Census map
Census region
Census subarea
Census tract
Census tract number
Central city
Central place
City
City and borough
Code
Collection block
Comunidad
Congressional district (CD)
Consolidated city
Consolidated metropolitan statistical area (CMSA)
County
County subdivision
Division (census geographic)
Extended city
Extended place
Geographic code
Geographic entity
Geographic hierarchy
Governmental unit (GU)
Hawaiian home land (HHL)
Incorporated place
Independent city
Independent place
Indian reservation
Island Areas
Joint use area
Legal entity
Metropolitan area (MA)
Metropolitan statistical area (MSA)
Minor civil division (MCD)
Municipality
Municipio
New England County Metropolitan Area (NECMA)
Off-reservation trust land
Oklahoma tribal statistical area (OTSA)
Outlying Areas
Parish
Place
Primary metropolitan statistical area (PMSA)
Pseudo-voting district (pseudo-VTD)
Public use microdata area (PUMA)
Region (census geographic)
Rural
School district
State
State designated American Indian statistical area (SDAISA)
State legislative district (SLD)
Statistical entity
Subbarrio
Sub-MCD
Super-PUMA
Tabulation block
Tabulation geography
Tract
Traffic analysis zone (TAZ)
Tribal block group
Tribal census tract
Tribal designated statistical area (TDSA)
Tribal jurisdiction statistical area (TJSA)
Tribal subdivision
Trust land
United States
Unorganized territory (UT)
Urban
Urban area
Urban cluster (UC)
Urban growth area (UGA)
Urbanized area (UA)
Voting district (VTD)
ZIP Code area
ZIP Code tabulation area (ZCTAa)
Zona urbana
Social Explorer; U.S. Census Bureau; Design and Methodology, American Community Survey. U.S. Government Printing Office, Washington, DC, 2009.