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

13. MSA (metropolitan statistical area),
14. categorical percent Hispanic or Latino in segment,
15. categorical percent black or African American in segment, and
16. categorical percent owner-occupied households in segment.
In some cases, due to the ages of the pair members, the education, employment status,
and marital status did not apply to one or both members of a pair. In order to increase the ability
to obtain convergent models, some of the cells in the categorical covariates were collapsed.
Additional variables defined in Section 6.2.3.2 were used to adjust the weights in the
final response models for each of the 11 age group pairs in those cases where the variables were
nonmissing. The variables follow:
1. number in household aged 0 to 11,
2. number in household aged 12 to 17,
3. number in household aged 18 to 25,
4. number in household aged 26 to 34,
5. number in household aged 35 to 49, and
6. number in household aged 50+.
In the cases where these variables were all nonmissing, they were put into the pool of
covariates for the final response model in place of HHSIZE. However, there were a handful of
cases for which these variables could not be determined. In those cases, 11 additional final
response models were fitted without the household composition age count variables listed above,
using the same pool of covariates that were used for the item response propensity models.
Building of models. For age group pairs 0 through 4 and 7 through 9, binary logistic
regression models were built. Since there were three outcomes with age group pairs 5, 6, and 10,
multinomial polytomous logistic models were fitted for these age group pairs. All the models
incorporated the design pair weights that were ratio adjusted for unit nonresponse (where a pair
was selected but did not respond to the survey) and calibrated to account for item nonresponse
(where a pair responded to the survey but the pair relationship was unknown), using the item
response propensity models, as described in Section 6.2.4.1. Naturally, not all of the covariates in
the original pool could be included in each model due to convergence problems. The final set of
covariates corresponding to each model is provided in Appendix Q.
Determination of predicted means. Although models were built using respondent pairs
where the pair relationship was known definitively, predicted probabilities were required for all
pairs. Once the models were fitted, predicted means were determined for both respondent pairs
and nonrespondent pairs, using the parameter estimates from the models.
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