Procuring honest responses indirectly

We propose a new method for obtaining truthful answers to sensitive survey questions indirectly from a dichotomous population. In the proposed method, each sample respondent is asked to report a numerical value chosen from two parallel set of multiple outcomes generated by arbitrary randomizing devices. We show that the proposed estimator of the population proportion is mon efficient and general than those put forward by Warner (1965. J. Amer. Statist. Assoc. 60, 63-69), Franklin (1989. Survey Methodol, 15, 225-235) and Kuk (1990. Biometrika 77, 436-438). Intuitively, our approach creates a remarkably respondent-friendly environment for each interviewee to discharge honest answers without the fear of exposing one's identity. Two illustrative cases using the normal and exponential distributions as randomizing devices are performed to demonstrate the superiority of the proposed estimator. (C) 2000 Elsevier Science B.V. All rights reserved. MSC: 62D05.