A qualified certainty: Verbal probability in arguments

Verbal Expressions of Confidence and Doubt

“…The rank ordering of the confidence expressions developed in this study support previous research finding that expressions of certainty fall along a continuum (Foley, 1959;Berry, 1960;Feezel, 1974;Fabre, 1991). The higherranked expressions convey greater confidence in a statement -what one knows to be true-and can be represented by expressions such as -I'm absolutely certain it's...." The more moderately-ranked confidence expressions convey less certainty in the accuracy of the statement, and are thus conveyed through expressions such as -I believe it's…."…”

“…For example, people might assign different numerical values to expressions such as -I am certain" and -I think," but they should always tend to rank -I am certain" as indicating more confidence than -I think. " Feezel (1974) suggests that terms of confidence lie along a continuum, and consistent results have been found for the positioning of words along this continuum, with terms such as suppose, think, sure, certain, and positive indicating increasing certainty (Foley, 1959;Berry, 1960;Fabre, 1991). These early studies, however, did not examine in depth how people express very low confidence, i.e., doubt.…”

“…Therefore, it may be advantageous for researchers examining the influence of verbal expressions of confidence to have access to a taxonomy of verbal expressions of confidence, to ensure consistent usage of terms and to know in advance how these terms are likely to be interpreted. With this aim in mind, a list of confidence expressions (interchangeable statements that are used either before or in conjunction with expressed judgments) was constructed using qualifiers and phrases identified in previous research as indicating different degrees of confidence, such as I know and I think (Foley, 1959;Berry, 1960;Feezel, 1974;Bradley, 1981;Westney, 1986;Furrow & Moore, 1990;Fabre, 1991;Pulford, 2002), akin to lists that have been created for verbal expressions of probabilities. The list incorporates hedges and disclaimers which occur in everyday language, covering the continuum from absolute certainty to complete doubt.…”

Context influences interpretation of eyewitness confidence statements.

“…Metacognition also plays a role when people assess the veracity of other people’s memories (sometimes called social metacognition; see, e.g., Frith, 2012; Jost, Kruglanski, & Nelson, 1998), although doing so involves making inferences based on other types of information, including the confidence that others express about their memory in words or demeanor. Indeed, research has shown that participants assign different strengths to a statement as a function of the vocabulary used by the information provider (e.g., Brun & Teigen, 1988; Feezel, 1974; Foley, 1959). For example, a person would be more likely to say that an individual who is “certain” an event occurred is more confident than a person who “supposes” the event occurred.…”