Questionnaire Dwelling Unit-Level and Person Pair-Level Sampling ...

4. Predictor Variables for the Questionnaire
Dwelling Unit and Pair Weight Calibration
via the Generalized Exponential Model
We note that unlike the person-level weight calibration, the control totals for the
questionnaire dwelling unit (QDU)-level and person pair-level poststratification are not available
from the U.S. Bureau of the Census. A way around this potential problem is to take advantage of
the two-phase nature of the design, in which the screener data provides a large sample containing
demographic information that can be used to derive control totals for the QDU-level and person
pair-level sampling weight calibrations, as well as for the selected person poststratification
adjustment. The stability of control totals from the screener dwelling unit (SDU)-level data can
be improved by poststratification of the SDU sample using person-level counts from the census.
This was indeed done and is documented in the person-level weight calibration report (Chen et
al., 2008).
4.1 QDU Weight Calibration
After the nonresponse and poststratification adjustments at the SDU level, which are
common to the person-level weight calibration, the QDU sample weights were adjusted in three
steps: poststratification of selected QDUs, nonresponse adjustment of respondent QDUs, and
poststratification of respondent QDUs. The set of initially proposed predictor variables for these
adjustments using generalized exponential model (GEM) were set to be common and to
correspond to those used for the SDU nonresponse and poststratification adjustments. The
variables are of two types: Those used for SDU nonresponse adjustment are 0/1 indicators, while
those used for SDU poststratification adjustment are counting variables. The variables of the first
type (0/1 indicators) are population density, group quarters, race/ethnicity of householder,
percentage of persons in segment who are black or African American, percentage of persons in
segment who are Hispanic or Latino, percentage of owner-occupied dwelling units (DUs) in
segment, segment-combined median rent and housing value, and household type. Variables of
the second type (counting variables) represent the number of eligible persons within each DU
who fall into the various demographic categories of race, age group, Hispanicity, and gender.
Note that the State and quarter variables are represented as both binary and counting variables.
Thus, not only are DU counts within a specific State or quarter in the QDU sample controlled to
the corresponding totals obtained from the SDU sample, but also counts of persons living in the
DUs in the QDU sample are controlled to totals from the SDU sample. These person-level totals
match the census estimates because of the SDU-level poststratification to census counts. It may
be noted that in the poststratification of selected QDUs and the nonresponse adjustment of the
respondent QDUs steps, demographic information from screener data was used in defining
covariates, whereas in the poststratification of the selected QDUs step, questionnaire
demographic information was used.
Exhibit 4.1 lists all predictor variables proposed for QDU-level calibration and identifies
them as counting, binary, or both. Various main effects and higher level factor effects based on
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