Details of Further Analysis

The regression models for this analysis were constructed to explore which demographic categories were most or least responsive to the respective probes. Since analyses could not be conducted on each item per se due to the small number of DK converts, all DK conversions across all items were combined for analyses. Logistic binary regressions were run such that the dependent variable was coded 1 for successful conversion by probe and 0 for unsuccessful conversion (that is, remained a DK response); and the independent variables were a series of dummy variables corresponding to demographic groups.