This short paper has important implications for those concerned with gaining the acceptance of forecasts. Wagenaar and Keren gave a five-minute test to 388 subjects. The results showed that the subjects acceptance of information depended upon the role that they were assigned. In this study, the roles were either that of an individual decision-maker ("a parent") or a societal decision-maker ("minister of traffic"). Half of the subjects were given each role and were provided with either anecdotal or statistical evidence on the need for seat belts in the back seats of automobiles. The anecdotal evidence was a three-sentence description of a traffic accident in which a 7-year old girl died because she died not wear a seat belt. [The description was not a vivid one.] The statistical evidence was provided by two sentences stating that 150 children die each year in motor vehicle accidents, and that this could be reduced to 50 if seat belts were used in the back seats. Although both groups of subjects were more influenced by the statistical data, the individual decisions-makers were relatively more impressed by the anecdotal evidence (39% saying they would purchase seat belts) than were the societal decision-makers (19% of whom would require the use of seat belts.) On the other hand, the societal decision-makers were relatively more influenced by the statistical evidence (62% favoring the use of seat belts, as compared with 47% of the individual decision-makers). You might argue that, in fact, two different decisions are being compared: whether to buy a seat belt oneself or whether to compel everyone to buy a seat belt. The results imply that 20% of the societal decision-makers would force others to purchase when they themselves would not purchase.
The study raises an issue that has not previously been dealt with extensively. Most of the research on judgment has examined individuals. Might their role in an organization affect the way they use forecasts? This should be fertile ground for further research.