Scholars increasingly rely on indirect
questioning techniques to reduce social desirability bias and item
nonresponse for sensitive survey questions. The major drawback of
these approaches, however, is their inefficiency relative to direct
questioning. We show how to improve the statistical analysis of the
list experiment, randomized response technique, and endorsement
experiment by exploiting auxiliary information on the sensitive
trait. We apply the proposed methodology to survey experiments
conducted among voters in a controversial anti-abortion referendum
held during the 2011 Mississippi General Election. By incorporating
the official county-level election results, we obtain precinct- and
individual-level estimates that are more accurate than standard
indirect questioning estimates and occasionally even more efficient
than direct questioning. Our simulation studies shed light on the
conditions under which our approach can improve efficiency and
robustness of estimates based on indirect questioning
techniques.
Open-source
software is available for implementing the proposed
methodology.