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

the predictor variables were included in the GEM modeling. As stated previously, all adjustment
steps at the QDU level used a common set of proposed predictor variables.
4.2 Pair Weight Calibration
Like QDU, the initial set of weight components in pair weight calibration are the same as
the set obtained from the SDU-level weight calibration. The SDU-calibrated weight is multiplied
by the pair-level design weight, which in turn was adjusted in four steps: poststratification of
selected pairs, nonresponse adjustment of respondent pairs, poststratification of respondent pairs,
and the extreme weight adjustment of respondent pairs. All the adjustment steps for pair weights
utilized the same set of initially proposed predictor variables, which included a subset of those
used for the person-level nonresponse adjustment. This included segment characteristic
variables, such as population density, percentage of persons in segment who are black or African
American, percentage of persons in segment who are Hispanic or Latino, percentage of owneroccupied
DUs in segment, and segment-combined median rent and housing value. Also included
were pair-specific covariates, such as the demographic characteristics of pair age, pair
race/ethnicity, and pair gender, as well as dwelling unit characteristics, such as race/ethnicity of
householder, household type, household size, and group quarters indicators. State and quarter
indicators were included as well. However, for two-factor effects, instead of individual State,
State/region was used due to insufficient sample size. This resulted in a 12-level variable where
the eight large sample States were kept separate, and the remainder of States were grouped
according to the four census regions. All variables were defined as 0/1 indicators. These
proposed predictor variables and their levels are shown in Exhibit 4.2.
In the poststratification of selected pairs and the nonresponse adjustment of respondent
pairs, screener data were used in the definition of the pair-specific variables such as pair age, pair
race/ethnicity, and pair gender, whereas in the poststratification and extreme weight adjustment
of respondent pairs, these variables were obtained from the questionnaire. For the latter case, in
addition to the variables described above, indicator covariates corresponding to selected pair
domains were included to perform Hajek-type ratio adjustments via weight calibration, as
mentioned in Chapter 1. The selected pair domains were limited to 10 of the 14 pair domains
listed in Chapter 1. (Parent-child pairs where the child was in the 15- to 17-year-old age range
and sibling-sibling-younger sibling focus pairs were not included in the poststratification.) The
inclusion of these pair domain covariates led to the use of two sets of control totals in the
modeling. Details of the construction of these control totals can be found in Appendix B.
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