A stochastic lie detector

Abstract

Surveys on sensitive issues provide distorted prevalence estimates when participants fail to respond truthfully. The randomized-response technique (RRT) encourages more honest responding by adding random noise to responses, thereby removing any direct link between a participant's response and his or her true status with regard to a sensitive attribute. However, in spite of the increased confidentiality, some respondents still refuse to disclose sensitive attitudes or behaviors. To remedy this problem, we propose an extension of Mangat's (Journal of the Royal Statistical Society: Series B, 56, 93-95, 1994) variant of the RRT that allows for determining whether participants respond truthfully. This method offers the genuine advantage of providing undistorted prevalence estimates for sensitive attributes even if respondents fail to respond truthfully. We show how to implement the method using both closed-form equations and easily accessible free software for multinomial processing tree models. Moreover, we report the results of two survey experiments that provide evidence for the validity of our extension of Mangat's RRT approach.

On the comprehensibility and perceived privacy protection of indirect questioning techniques

“…Regarding thorough examination of the validity of indirect questioning, in some strong validation studies, RRT estimates deviated substantially from known population values (e.g., Kulka et al, 1981;van der Heijden, van Gils, Bouts, & Hox, 2000). These results might be explained in terms of participants' noncompliance with instructions even under RRT conditions, especially concerning surveys that cover highly INDIRECT QUESTIONS: COMPREHENSIBILITY AND PRIVACY 10 sensitive personal attributes (e.g., Clark & Desharnais, 1998;Edgell, Himmelfarb, & Duchan, 1982;Moshagen et al, 2012). Two psychological aspects that are likely to play a role in respondents' willingness to cooperate are a) the ability to understand instructions and b) whether respondents trust the promise of confidentiality associated with use of indirect questioning.…”

“…The CDM (Clark & Desharnais, 1998) and the SLD (Moshagen et al, 2012) allow for a separate estimation of the proportion of noncompliant respondents in the sample by implementing an additional cheating parameter. The CWM (Yu et al, 2008) is presumably easier to understand than other RRT models and offers a symmetric design, which might facilitate honest responding.…”

Misunderestimating Corruption

“…However, there is one feature of an RRQ that provides opportunities for uses different from the intentions of its designers-the randomization probability embodied in the question affects the relationship between reticence and responses. Using this insight, Clarke and Deshairnais (1998), , and Moshagen, Musch, and Erdfelder (2012) suggest creating subsamples of respondents and asking them RRQs with different randomization probabilities. They then derive insights into levels of reticence and guilt.…”

A discussion of the two different aspects of privacy protection in indirect questioning designs

“…Recently, Chaudhuri (2011), Chaudhuri andChristofides (2013), and Chaudhuri et al (2016) wrote or edited books on the various aspects of the indirect questioning procedures. Their practical use in surveys on different sensitive subjects is well documented (see for instance, van den Hout et al 2010;Krumpal 2012;Moshagen et al 2012;Kirchner et al 2013;De Hon 2014). Their effect on the data quality was also investigated in several studies with quite different results, which mainly underlines the sensitivity of such surveys to a great many aspects with the privacy protection of respondents among them (cf., for instance, LensveltMulders et al 2005LensveltMulders et al , 2006Holbrook and Krosnick 2010;Coutts and Jann 2011;Jann et al 2012;Wolter and Preisendörfer 2013;Höglinger et al 2014;Höglinger and Diekmann 2017).…”