1. David A. Swanson University of California Riverside David.swanson@ucr.edu The American Community Survey: Some Considerations Regarding its use as a Substitute for the Sample ‘Long Form’ in the Decennial US Census

2. OUTLINE OVERVIEW. BASIC CENSUS PRINCIPLES BASIC PRINCIPLES & THE US DECENNIAL CENSUS ACS & THE 2010 DECENNIAL CENSUS BASIC PRINCIPLES & THE ACS USED AS THE ‘LONG FORM’ SUMMARY

3. OVERVIEW As did its post-WWII predecessors, the 2000 decennial census had two parts: 1) the short form, which was used to enumerate the population; and 2) the long form, which obtained demographic, housing, social, and economic information from a 1-in-6 sample overall.

4. OVERVIEW The sample long form data were ‘adjusted’ in order to make them consistent with the short form data and although inconsistencies abounded, the result was intended to provide a census with a ‘one number roll- up’ The sample long form data were ‘adjusted’ in order to make them consistent with the short form data and although inconsistencies abounded, the result was intended to provide a census with a ‘one number roll- up’

5. OVERVIEW The American Community Survey (ACS) was designed as a way to provide the data communities need more frequently than once every ten years. It also is intended to serve as a ‘substitute’ for the ‘long form’ in the 2010 Census.

6. OVERVIEW The ACS represents an alternative to the traditional model of the census by means of a continuous cumulative survey covering the whole country over a long period of time (generally years), rather than a particular day or short period of enumeration, as was the case for the decennial long form sample and as is the case still for the decennial short form 100% enumeration. The ACS represents an alternative to the traditional model of the census by means of a continuous cumulative survey covering the whole country over a long period of time (generally years), rather than a particular day or short period of enumeration, as was the case for the decennial long form sample and as is the case still for the decennial short form 100% enumeration.

7. OVERVIEW The American Community Survey provides estimates of demographic, housing, social, and economic characteristics every year for all states, as well as for all cities, counties, metropolitan areas, and population groups of 65,000 people or more.

8. OVERVIEW For smaller areas, it takes three to five years to accumulate sufficient sample to produce data for areas as small as census tracts. For areas of 20,000 to 65,000, the date will be cumulated over three years. For rural areas and city neighborhoods or population groups of less than 20,000 people, it will take five years to accumulate a sample that is similar to that of the decennial census. Virtually every census tract and block group falls into the ‘five year’ segment.

9. OVERVIEW Given that the ACS is presented as a substitute for the long form, it is worthwhile to consider how it differs from the decennial census. Given that the ACS is presented as a substitute for the long form, it is worthwhile to consider how it differs from the decennial census. It is appropriate to start with the recommendations and principles promulgated by the United Nations in regard to data collection for purposes of a census. It is appropriate to start with the recommendations and principles promulgated by the United Nations in regard to data collection for purposes of a census.

10. BASIC CENSUS PRINCIPLES On page 8 of its manual, Principles and Recommendations for Population Censuses, The United Nations (2007) describes four essential features of population and housing censuses: On page 8 of its manual, Principles and Recommendations for Population Censuses, The United Nations (2007) describes four essential features of population and housing censuses: (1) individual enumeration; (1) individual enumeration; (2) universality within a defined region; (2) universality within a defined region; (3) simultaneity; and (3) simultaneity; and (4) defined periodicity. (4) defined periodicity.

11. BASIC CENSUS PRINCIPLES (1) Individual Enumeration Separate information is collected regarding the characteristics of each individual. Separate information is collected regarding the characteristics of each individual.

12. BASIC CENSUS PRINCIPLES (2) Universality within a Defined Territory All persons within the defined territory who meet the coverage rules are enumerated. All persons within the defined territory who meet the coverage rules are enumerated.

13. BASIC CENSUS PRINCIPLES (3) Simultaneity Information is extracted as it reflects the situation of individuals at the census moment in time. Information is extracted as it reflects the situation of individuals at the census moment in time.

14. BASIC CENSUS PRINCIPLES (4) Periodicity Extracts meeting the other three essential features (Individual enumeration, universality, and simultaneity) can be taken at a desired frequency, including “at least once in 10 years…” Extracts meeting the other three essential features (Individual enumeration, universality, and simultaneity) can be taken at a desired frequency, including “at least once in 10 years…”

15. BASIC PRINCIPLES & THE US DECENNIAL CENSUS (1) Individual Enumeration (1) Individual Enumeration The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because separate information was collected regarding the characteristics of each individual. The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because separate information was collected regarding the characteristics of each individual. Its ‘short form’ is currently consistent with this principle. Its ‘short form’ is currently consistent with this principle.

16. BASIC PRINCIPLES & THE US DECENNIAL CENSUS (2) Universality within a Defined Region (2) Universality within a Defined Region The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because all persons within the defined territory who meet the coverage rules are enumerated. The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because all persons within the defined territory who meet the coverage rules are enumerated. Its ‘short form’ is currently consistent with this principle. Its ‘short form’ is currently consistent with this principle.

17. BASIC PRINCIPLES & THE US DECENNIAL CENSUS (3) Simultaneity (3) Simultaneity The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because information was extracted as it reflected the situation of individuals at the census moment in time. The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because information was extracted as it reflected the situation of individuals at the census moment in time. Its ‘short form’ is currently consistent with this principle. Its ‘short form’ is currently consistent with this principle.

18. BASIC PRINCIPLES & THE US DECENNIAL CENSUS (4) Defined Periodicity. (4) Defined Periodicity. The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because extracts meeting the other three essential features (Individual enumeration, universality, and simultaneity) were taken at a desired frequency, which was once in 10 years. The US Decennial Census was consistent with this principle in both its historical ‘long form’ and its historical ‘short form because extracts meeting the other three essential features (Individual enumeration, universality, and simultaneity) were taken at a desired frequency, which was once in 10 years. Its ‘short form’ is currently consistent with this principle.

19. BASIC PRINCIPLES & THE US DECENNIAL CENSUS The US Decennial Census was consistent with UN Recommendations in both its historical ‘long form’ and its historical ‘short form because together they met the principles of: The US Decennial Census was consistent with UN Recommendations in both its historical ‘long form’ and its historical ‘short form because together they met the principles of: (1) individual enumeration; (1) individual enumeration; (2) universality within a defined region; (2) universality within a defined region; (3) simultaneity; and (3) simultaneity; and (4) defined periodicity. (4) defined periodicity.

20. ACS & THE 2010 CENSUS In the September 20 th, 2010 issue of the Federal Register (pp. 57254-57257) the US Census Bureau announced its plans to provide small-area data similar to the data published after Census 2000, based In the September 20 th, 2010 issue of the Federal Register (pp. 57254-57257) the US Census Bureau announced its plans to provide small-area data similar to the data published after Census 2000, based on the long-form sample. on the long-form sample. The Bureau states that it would use ACS 5-year data products covering the period of 2005–2009 for this purpose and described how the 2005-2009 ACS data would be modified so that they could be used in a manner similar to the 2000 census long-form sample. The Bureau states that it would use ACS 5-year data products covering the period of 2005–2009 for this purpose and described how the 2005-2009 ACS data would be modified so that they could be used in a manner similar to the 2000 census long-form sample.

21. BASIC PRINCIPLES & THE ACS USED AS THE ‘LONG FORM’ (1) Individual Enumeration (1) Individual Enumeration Used as a substitute for the Decennial ‘Long Form,’ the ACS is consistent with this principle. Used as a substitute for the Decennial ‘Long Form,’ the ACS is consistent with this principle.

22. BASIC PRINCIPLES & THE ACS USED AS THE ‘LONG FORM’ (2) Universality within a Defined Region (2) Universality within a Defined Region Used as a substitute for the Decennial ‘Long Form,’ the ACS is consistent with this principle in that it is composed of a a sample of the entire US, as was the case of the Decennial ‘Long Form.’ Used as a substitute for the Decennial ‘Long Form,’ the ACS is consistent with this principle in that it is composed of a a sample of the entire US, as was the case of the Decennial ‘Long Form.’ However, it is not consistent with the short form in that its coverage rules (2 month residency) are not the same as the coverage rules used in the Decennial Census Short Form (place of usual residence). However, it is not consistent with the short form in that its coverage rules (2 month residency) are not the same as the coverage rules used in the Decennial Census Short Form (place of usual residence).

23. BASIC PRINCIPLES & THE ACS USED AS THE ‘LONG FORM’ (3) Simultaneity (3) Simultaneity Used as a substitute for the Decennial ‘Long Form,’ the ACS is not consistent with this principle because information is not extracted as it reflects the situation of individuals at the census moment in time, as described in the Federal Register of September 20 th, 2010. Used as a substitute for the Decennial ‘Long Form,’ the ACS is not consistent with this principle because information is not extracted as it reflects the situation of individuals at the census moment in time, as described in the Federal Register of September 20 th, 2010.

24. BASIC PRINCIPLES & THE ACS USED AS THE ‘LONG FORM’ 4) Defined Periodicity. Used as a substitute for the Decennial ‘Long Form,’ the ACS is not consistent with this principle because: (1) extracts from it do not meet all of the other three essential features (Individual enumeration, universality, and simultaneity); (2) the entire ACS is not taken at the same frequency as the Decennial Census, which is once every ten years; and (3) the Census Bureau’s plan (as specified in the Federal Register of September 20 th, 2010 and outlined in Dr. Groves’ talk to the National Press Club on November 1 st ), suggests that the ACS will be largely divorced from the 2010 Census. Used as a substitute for the Decennial ‘Long Form,’ the ACS is not consistent with this principle because: (1) extracts from it do not meet all of the other three essential features (Individual enumeration, universality, and simultaneity); (2) the entire ACS is not taken at the same frequency as the Decennial Census, which is once every ten years; and (3) the Census Bureau’s plan (as specified in the Federal Register of September 20 th, 2010 and outlined in Dr. Groves’ talk to the National Press Club on November 1 st ), suggests that the ACS will be largely divorced from the 2010 Census.

25. SUMMARY Now, I leave you with a question. Now, I leave you with a question. Considering the differences between the ACS and the Decennial Census in terms of the four fundamental census principles what do you foresee as the effect of having the ACS as a replacement for the long form in the 2010 Census not only on general users, but on researchers in terms of modeling and analysis? Considering the differences between the ACS and the Decennial Census in terms of the four fundamental census principles what do you foresee as the effect of having the ACS as a replacement for the long form in the 2010 Census not only on general users, but on researchers in terms of modeling and analysis?