© John M. Abowd 2005, all rights reservedUsing the Decennial Census of Population and HousingJohn M. AbowdFebruary 2005© John M. Abowd 2005, all rights reservedOutline• Census 2000• Hundred Percent Detail File (short form)• Sample Detail Edited File (long form)• Record Structure• Identifiers• Linking Block, Household and Person-level data• Example Problems© John M. Abowd 2005, all rights reservedCensus 2000• Target Population:– All residents living in housing units or group quarters within the United States and its territories plus individuals living abroad with usual residence in the same geography• Methods:– Short form: universal questionnaire by mail and follow-up– Long form: approximately 1/6 sample of households© John M. Abowd 2005, all rights reservedEnumeration Population• Enumeration rules. Each person whose usual residence was in the United States was to be included in the census, without regard to the person’s legal status or citizenship. As in previous censuses, people specifically excluded from the census were citizens of foreign countries temporarily traveling or visiting in the United States who had not established a residence. Americans temporarily overseas were to be enumerated at their usual residence in the United States. With some exceptions, Americans with a usual residence outside the United States were not enumerated in Census 2000. U.S. military personnel and federal civilian employees stationed outside the United States and their dependents living with them, are included in the population counts for the 50 states for purposes of Congressional apportionment but are excluded from all other tabulations for states and their subdivisions. The counts of overseas U.S. military personnel, federal civilian employees, and their dependents were obtained from administrative records maintained by the employing federal departments and agencies. Other Americans living overseas who were not affiliated with the U.S. government were not included in the census.• Summary File 3, Technical Documentation Pages C-1, C-2© John M. Abowd 2005, all rights reservedHundred Percent Detail File (HDF)• Contains edited information from the short form• Used for all official publications– Summary files– Special tabulations– Public Use Micro Samples (PUMS)© John M. Abowd 2005, all rights reservedSample Detail Edited File• Contains information from the long form• Used for all official publications that contain long form data– Summary files– Special tabulations– Public Use Micro Samples (PUMS)© John M. Abowd 2005, all rights reservedRecord Structure• Applies to HDF and SDEF• Hierarchy maintained as separate files– Block level data– Housing unit data– Person data associated with housing units– Group quarters data (not RDC accessible)– Person data associated with group quarters (not RDC accessible)© John M. Abowd 2005, all rights reservedIdentifiers• Geography (Block data)• Household (Housing unit data)• Group quarters (Group quarters data)• Person (Individual data)© John M. Abowd 2005, all rights reservedGeographic Identifiers• Located on the Block-level file• Called Record type 1• A complete identifier:– State (Char 2)– County (Char 3)– Tract (Char 6)– Block (Char 4)© John M. Abowd 2005, all rights reservedHousing Unit Identifier• On the housing unit record• Called record type 2• A complete identifier:– MAFID (Char 12)© John M. Abowd 2005, all rights reservedGroup Quarters Identifier• On the group quarters record (not in RDCs)• Called record type 4• A complete identifier:– MAFID (Char 12)© John M. Abowd 2005, all rights reservedPerson Identifier• On the housing unit person (record type 3) and group quarters person (record type 5)• Group quarters persons not available in RDCs• A complete identifier:– PUID (Char 13)– PSEQ (Char 2)– PNC (Char 5)© John M. Abowd 2005, all rights reservedLinking Records• Use the unique identifier to relate block, housing and person-level data• Use the appropriate definitions to construct geographic aggregates and housing aggregates© John M. Abowd 2005, all rights reservedExample• Lab 4 exercise applied to internal Census