Assessing Deception Detection Accuracy with Dichotomous Truth–Lie Judgments and Continuous Scaling: Are People Really More Accurate When Honesty Is Scaled?

Abstract

Deception detection experiments consistently find that people are only slightly better than chance at distinguishing truths from lies. Interpersonal deception theory research, however, claims that people can accurately detect deception when honesty is assessed with continuous scaling. This article reports an experiment (N = 140) directly testing if the type of measurement meaningfully impacts accuracy results and conclusions. The findings suggest that the difference is largely illusory, and that the differences that are observed are attributable to differential variances in the measures. Substantively, both methods yield similar conclusions including slightly better-than-chance accuracy, persistent truth bias, and a robust veracity effect.