Certainty improves the predictive validity of Honesty-Humility and Dark Triad traits on cheating behavior

This research examined the extent to which certainty can strengthen the relationship between individual differences and cheating behavior. In the first two studies, participants completed the Honesty-Humility or the Dark Triad scales. Then, they rated the certainty they had in their responses to each of those two inventories. In the third study, participants completed both scales within the same experimental design and were randomly assigned to a certainty vs. doubt condition. As the dependent variables, we used different cheating outcomes across studies. As predicted, the link between these two traits and cheating behavior was greater for participants with higher levels of certainty in their responses to the inventories (Studies 1 and 2) or for those assigned to the certainty (vs. doubt) condition (Study 3). Incorporating the certainty with which individuals hold their traits contributes to enhancing the predictive validity of personality measures relevant to cheating.