Public Use Microdata Sample, Guam 2000 Issued May 2004 2000 Census of Population and Housing PUMS/02-GUAM Technical Documentation U.S. Department of Commerce Economics and Statistics Administration U.S. CENSUS BUREAU For additional information concerning the files, contact Marketing Services Office, Customer Services Center, U.S. Census Bureau, Washington, DC 20233 or phone 301-763-INFO (4636). For additional information concerning the technical documentation, contact Administrative and Customer Services Division, Electronic Products Development Branch, U.S. Census Bureau, Washington, DC 20233 or phone 301-763-8004. U.S. Census Bureau Public Use Microdata Sample, Guam 2000 Issued May 1004 2000 Census of Population and Housing PUMS/02-GUAM Technical Documentation U.S. Department of Commerce Donald L. Evans, Secretary Samuel W. Bodman, Deputy Secretary Economics and Statistics Administration Kathleen B. Cooper, Under Secretary for Economic Affairs U.S. CENSUS BUREAU Charles Louis Kincannon, Director SUGGESTED CITATION FILES: Census 2000, Public Use Microdata Sample, (PUMS), Guam, prepared by the U.S. Census Bureau, 2003 TECHNICAL DOCUMENTATION: Census 2000, Public Use Microdata Sample, (PUMS), Guam, Technical Documentation, prepared by the ECONOMICS U.S. Census Bureau, 2003 AND STATISTICS ADMINISTRATION Economics and Statistics Administration Kathleen B. Cooper, Under Secretary for Economic Affairs U.S. CENSUS BUREAU Cynthia Z.F. Clark, Charles Louis Kincannon, Associate Director for Methodology and Director Standards Hermann Habermann, Marvin D. Raines, Deputy Director and Associate Director Chief Operating Officer for Field Operations Vacant, Arnold A. Jackson, Principal Associate Director Assistant Director and Chief Financial Officer for Decennial Census Vacant, Principal Associate Director for Programs Preston Jay Waite, Associate Director for Decennial Census Nancy M. Gordon, Associate Director for Demographic Programs CONTENTS Chapters 1. Abstract ................................. 1–1 2. Introduction ............................... 2–1 3. How to Use This File........................... 3–1 4. Accuracy of the Microdata Sample Estimates .............. 4–1 5. Sample Design and Estimation ..................... 5–1 6. Data Dictionary ............................. 6–1 7. User Updates .............................. 7–1 Appendixes A. Census 2000 Geographic Terms and Concepts............. A–1 B. Definitions of Subject Characteristics.................. B–1 C. Data Collection and Processing Procedures .............. C–1 D. Questionnaire .............................. D–1 E. Data Products and User Assistance ................... E–1 F. Maps ................................... F–1 G. Code Lists ................................ G–1 H. Topcoded Variables and Control Counts ................ H–1 iii Chapter 1. Abstract CITATION U.S. Census Bureau, 2000 Census of Population and Housing, Public Use Microdata Sample, Guam: Technical Documentation, 2003. TYPE OF FILE Microdata SUBJECT CONTENT The Public Use Microdata Sample (PUMS) file contains records representing a 10-percent sample of the occupied and vacant housing units in Guam and the people in the occupied units. Group quar- ters people also are included. The file contains a weight of 10 for each person and housing unit, which when applied to the individual records, expand the sample to the relevant total. Please see Chapter 6, Data Dictionary for a complete list of the variables and recodes. Some of the items included on the housing record are: air conditioning; allocation flags for hous- ing items; bathroom facilities; bedrooms; condominium fee; condominium status; contract rent; cooking facilities; cost of utilities; family income in 1999; household income in 1999; household type; housing unit weight; material for walls, roof, and foundation; mortgage payment; mortgage status; piped water; presence and age of own children; presence of subfamilies in household; radio; real estate taxes; refrigerator; rooms; selected monthly owner costs; sewage disposal; sink; size of building (units in structure); source of water; state code; telephone service; tenure; vacancy status; value (of housing unit); vehicles available; year householder moved into unit; and year structure built. Some of the items included on the person record are: allocation flags for population items; citizen- ship; class of worker; disability status; earnings in 1999; educational attainment; father’s place of birth; fertility; grandparents as caregivers; hours worked; income in 1999 by type; industry; lan- guage spoken at home; marital status; means of transportation to work; migration state; mobility status; mother’s place of birth; veteran period of service; years of military service; occupation; per- son’s weight; personal care limitation; place of birth; place of work state; poverty status in 1999; race/ethnicity; relationship; school enrollment and type of school; time of departure for work; travel time to work; vehicle occupancy; weeks worked in 1999; work limitation status; work sta- tus in 1999; and year of entry. GEOGRAPHIC CONTENT The 2000 PUMS file for Guam covers the island of Guam and does not contain any sub-island geography. USER UPDATES The section on User Updates informs data users about corrections, errata, and related explanatory information. However, sometimes this information becomes available too late to be reflected in this related documentation. The most up-to-date compilation of Census 2000 user updates is available on the Census Bureau’s Internet site at www.census.gov/main/www/cen2000.html. Users also can register to receive user updates by e-mail by contacting Customer Services Center, Marketing Services Office, U.S. Census Bureau on 301-763-INFO (4636) ([email protected]). FILE ORDERING For ordering and pricing information, access the online catalog at the Census Bureau’s Internet site (www.census.gov) or contact the Census Bureau’s Customer Services Center (301-763-INFO (4636)). Abstract 1–1 U.S. Census Bureau, Census 2000 Chapter 2. Introduction OVERVIEW Public use microdata sample files are ASCII files that contain individual records of the characteris- tics for a sample of people and housing units. Information that could identify a household or an individual is excluded in order to protect the confidentiality of respondents. Within the limits of the sample size, the geographic detail, and the confidentiality protection, these files allow users to prepare virtually any tabulation they require. WHAT ARE MICRODATA? Microdata are the individual records that contain information collected about each person and housing unit. They include the census basic record types, computerized versions of the question- naires collected from households, as coded and edited during census processing. The Census Bureau uses these confidential microdata in order to produce the summary data that go into the various reports, summary files, and special tabulations. Public use microdata samples are extracts from the confidential microdata taken in a manner that avoids disclosure of information about households or individuals. For Census 2000, the microdata are only available to the public through the Public Use Microdata Sample (PUMS) products. PROTECTING CONFIDENTIAL INFORMATION All data released (in print or electronic media) by the Census Bureau are subject to strict confiden- tiality measures imposed by the legislation under which our data are collected: Title 13, U.S. Code. Responses to the questionnaire can be used only for statistical purposes, and Census Bureau employees are sworn to protect respondents’ identities. Because of the rapid advances in computer technology since 1990 and the increased accessibility of census data to the user community, the Census Bureau has had to adopt more stringent mea- sures to protect the confidentiality of public use microdata through enhanced disclosure limitation techniques. Confidentiality is protected, in part, by the use of the following processes: data-swapping, topcod- ing of selected variables, geographic population thresholds, age perturbation for large house- holds, and reduced detail on some categorical variables. Data swapping is a method of disclosure limitation designed to protect confidentiality in tables of frequency data (the number or percent of the population with certain characteris- tics). Data swapping is done by editing the source data or exchanging records for a sample of cases. Swapping is applied to individual records and, therefore, also protects microdata. Top-coding is a method of disclosure limitation in which all cases in or above a certain per- centage of the distribution are placed into a single category. Geographic population thresholds prohibit the disclosure of data for individuals or housing units for geographic units with population counts below a specified level. Age perturbation, that is, modifying the age of household members, is required for large households (households containing ten people or more) due to concerns about confidentiality. Detail for categorical variables is collapsed if the number of occurrences in each category does not meet a specified national minimum threshold. To maintain confidentiality, while retaining as much characteristic detail as possible, a minimum threshold of 30 nationally is set for the identification of variable categories within categorical vari- ables in the 10-percent PUMS file. Introduction 2–1 U.S. Census Bureau, Census 2000 USES OF MICRODATA FILES Public use microdata files essentially