When (and Why) Expressing Uncertainty Affects Perceptions of Competence

Abstract

What do we infer about others’ when they express uncertainty? A broad literature on this question has yielded results that appear contradictory. In prior work, expressing more (versus less) certainty has been associated with being perceived as being both more and less competent. In this paper, I propose and test a theory to reconcile these findings. I argue that people make inferences about others on the basis of fit between the amount of certainty that those others express and their own beliefs about the epistemicness (predictability) of the environment. Fit between expressed certainty and perceived epistemicness suggests calibration and in turn competence. I find support for this account across four experimental studies involving both real and hypothetical communication. In each study, I manipulate two factors: the amount of certainty that an advisor or teammate expresses and a characteristic that affects the epistemicness of a given prediction or estimation. Participants display a preference for others who express more certainty in more epistemic environments, but this preference attenuates (S1a, S1b) or reverses (S2, S3) in less epistemic environments. This pattern is explained by participants’ perceptions of the epistemicness of each environment.