| This paper examined individual and group level layperson decision making when information from multiple experts is available. A total of 767 participants read four scenarios with various forms of expert advice, and then made decisions and gave confidence ratings. As expert advice format became more precise (ambiguous statements to numerical probabilities), individuals and groups tended to make more nearly optimal decisions, with higher consensus across decision makers. However, decision confidence and satisfaction peaked when expert advice was in a verbal form, which was not the most precise form. In a surprising contrast to most group research, group level confidence ratings did not differ significantly from those of individual decision makers, nor did groups make substantially better decisions. Implications of these results for selection of expert advisor presentation format are discussed. |
