Verbal expressions of confidence and doubt.

The development of a taxonomy of expressions expressing the degree of confidence or certainty felt in the correctness of one's judgments, knowledge, or beliefs is reported. 30 phrases expressing confidence and doubt were rated by 96 British participants on a 7-point scale to indicate how much confidence or doubt they felt each phrase expressed. The expressions were rank ordered, based on their mean ratings, to produce a continuum of cues expressing confidence, ranging from high to low. 9 of the 30 expressions were rated as expressing lower confidence when phrased in the past tense than in the present tense. The expressions reported in this study form a useful tool for researchers who are investigating the communication of confidence and degrees of belief, especially in relation to giving advice, influence, and persuasion.