2 August 2001
Symposium on Global Review of 2000 Round of
Population and Housing Censuses:
Mid-Decade Assessment and Future Prospects
Department of Economic and Social Affairs
United Nations Secretariat
New York, 7-10 August 2001
Statement from United States of America *
1. The United States Census Bureau implemented a series of initiatives to involve important census stakeholders in the planning and implementation of Census 2000. Principal among these activities was the establishment of the Census 2000 advisory committees in 1995, which continue meeting to this day. The committees are made up of representatives of organizations from across the nation who have a variety of concerns and interests about the design and accuracy of the census. They meet quarterly in public meetings to review reports and presentations by representatives from the Census Bureau, Department of Commerce, and other public and private organizations. They also formed working groups on selected topics, and their members held a series of separate meetings with Census Bureau staff to develop recommendations on those topics. The Census 2000 advisory committees provided a targeted review of Census 2000 operations from the perspective of census stakeholders outside of the Census Bureau, and they made important, substantive contributions on Census 2000 research, design and policy issues.
2. The Census Bureau also implemented a far-reaching marketing and promotion effort, which was enhanced by the establishment of the Census 2000 partnership programme. The Census Bureau developed more than 100,000 partnerships with a wide range of government and non-government organizations at the national and local levels. These partners served as trusted agents in their communities, and they were helpful in assisting the Census Bureau in the effort to reach people in hard-to-enumerate areas.
3. The United States constitution requires that the United States conduct an enumeration of the resident population every 10 years. Consequently, the Census Bureau’s data-collection operations for the decennial census are oriented towards fulfilling this mandate as accurately as possible. For Census 2000, the Census Bureau used three basic data-collection methods: mailout/mailback (where the Census Bureau mailed questionnaires to housing units on the address list and residents mailed them back), update/leave (where Census Bureau workers delivered questionnaires while simultaneously updating the address list) and list/enumerate (where Census Bureau enumerators created the address list while canvassing their assignment areas and conducted interviews with respondents). Individuals also had the opportunity to respond to the census through the Internet or by telephone, and the “Be Counted” programme provided additional means for people to be included in the census by allowing them to fill out a blank form made available in various public locations. In addition, special enumeration procedures were followed for remote parts of Alaska, for locations containing a concentration of persons with a transient lifestyle (for example, trailer parks, marinas and campgrounds), for group quarters (prisons, long-term care facilities and the like) and for people with no usual residence.
4. After allowing a reasonable amount of time for respondents to mail back their questionnaires, the Census Bureau conducted an operation called non-response follow-up (NRFU), during which census field staff followed up with housing units that did not return their questionnaires by mail. A census enumerator made up to six attempts to contact housing units that appeared occupied to secure an interview. If an interview could not be obtained, the enumerator attempted to interview a neighbour, building manager or other knowledgeable individual. A number of other operations were implemented to ensure that coverage was as complete as possible in the initial operation, and all major Census 2000 operations were subjected to quality-assurance activities designed to detect and correct errors before they affected the accuracy or quality of the data. Once data-collection activities were complete, the Census Bureau conducted an accuracy and coverage evaluation to examine the quality of the Census 2000 counts.
5. The success of Census 2000 was due, in part, to a significant expansion in the application of new technologies. This expansion included a revolution in image-capture capability, expanded use of the Internet and the use of laptop computers for some data-collection activities. In partnership with its contractors, the Census Bureau developed the Data Capture System 2000, which used the latest commercial technology available. Automatic sorters were used to sort the questionnaires by questionnaire categories, and the questionnaires were scanned to obtain electronic images of the responses. Optical-character recognition software was then used to capture approximately 75 per cent of the write-in questions without need for further human intervention. In addition, optical-mark recognition software captured 100 per cent of the check-box questions on the long and short forms. Data were then transmitted to the computers at Census Bureau headquarters where the data were verified and tabulated.
6. In the coming decade the Census Bureau is planning an even greater expansion in the use of technology for doing the census. This effort will integrate three components: collecting long-form data monthly in a national survey called the American Community Survey (ACS); enhancing the master address file and the Census Bureau’s geographic database (described below); and a re-engineered 2010 short form census to take advantage of these improvements by automating operations that were previously conducted manually. Research and testing will involve exploring the possibility of using portable computers equipped with global positioning systems for updating the address list and for use in non-response and other field follow-up activities. The Census Bureau also will examine methods for expanding the Internet and other electronic reporting options for data collection.
7. After the 1980 census, the Census Bureau initiated the development of a single, integrated, automated geographic database that covers the areas for which it takes censuses and surveys. The goal is a database that: 1) links every living quarter—that is, every housing unit and group quarters—to its correct geographic entities; 2) provides the maps and geographic controls needed for the Census Bureau’s collection, tabulation and dissemination of census data; and 3) can be updated relatively quickly and easily to reflect new information obtained from various operations. The result is the Topologically Integrated Geographic Encoding and Referencing (TIGER7) File, which is now referred to as the TIGER database. Essentially, this is a computer-readable, seamless map of the United States, Puerto Rico, and the island areas that are covered by the decennial census and other Census Bureau surveys. Census Bureau staff use the TIGER database to fulfill the majority of census mapping operations, including the following:
· Cataloguing and identifying the relationships between the geographic entities for which data are collected, tabulated and disseminated;
· Geocoding addresses so that they are accurately assigned to these entities; and
· Producing a variety of census maps that correctly display census geography.
8. In addition to recording basic map features in their correct locations, the database:
· Includes the names of many features, such as streets and bodies of water;
· Contains city-style address ranges, compatible with a file of mailing addresses, for those street segments whose living quarters have addresses that use a house number and street name for mail delivery; and,
· Identifies, and delineates the boundaries of, every geographic entity for which the Census Bureau collects and tabulates data.
9. The enumeration planning process for the decennial census is a continual process of research and testing. As new data-collection methodologies are identified, implementation is tested in the various tests scheduled for the decade. The Census Bureau conducts focused, special-purpose tests in small areas of the country or small segments of the population to establish feasibility. The formal tests are broader in scope, including aspects of all census processes, and are conducted to the extent possible in the full census context. The sites for these formal tests usually consist of both medium-sized cities and rural counties. Formal evaluation programmes are designed to measure the outcomes of the objectives being tested.
10. The United States Census Bureau has a major, permanent directorate for the decennial census. It has an associate director, assistant directorate and four divisions that supply programme management and coordination; statistical support; geographic and address list resources; and automation, technology, processing and contracting operations. In addition, the directorate draws heavily on other divisions to supply support in the areas of subject matter, information technology (IT), infrastructure, data collection and other areas.
11. For at least the last two decennial censuses of the United States, the Census Bureau has begun planning for the next census while conducting the current census. For example, planning for Census 2000 began as a small effort in 1987, which was expanded in 1991 and grew steadily over the decade. This enabled the Census Bureau to move staff experienced in the current census to work on the next census with some expedience. The Census Bureau has learned that it is critical to develop staff between censuses in order to take full advantage of the knowledge and experience gained in each decennial effort. This is particularly important as new technologies become available which present opportunities for increased efficiencies in census-taking operations.
12. It is also beneficial to maintain critical records—documented plans, requirements, and specifications; field and processing materials; correspondence and reports; and evaluation data—from census to census. These records are valuable in supplementing the human institutional knowledge that may be lost due to attrition of key personnel; to avoid duplication of effort in planning or implementing procedures, where applicable; and as a “starting point” for producing materials for the next census. Prior to Census 2000, Census Bureau staff tried to establish paper libraries and a record of electronic files, to maintain these records. Due to changes in personnel and organization, this had mixed success. For 2010, the Census Bureau is developing an electronic library of all such material, maintained in a central database.
* This document was reproduced without formal editing.
U.S. Census Bureau, United States of America. The views expressed in the paper are those of the author and do not imply the expression of any opinion on the part of the United Nations Secretariat.