Further notes on public response to uncertainty in risks and science.

Given the prevalence of uncertainty and variability in estimates of environmental health risks, it is important to know how citizens interpret information representing uncertainty in risk estimates. Ranges of risk estimates from a hypothetical industry source elicited divergent evaluations of risk assessors' honesty and competence among New Jersey residents within one mile of one or more factories. A plurality saw ranges of risk estimates as both honest and competent, but with most judging such ranges as deficient on one or both dimensions. They wanted definitive conclusions about safety, tended to believe the high end of the range was more likely to be an accurate estimate of the risk, and believed that institutions only discuss risks when they are "high." Acknowledgment of scientific, as opposed to self-interested, reasons for uncertainty and disputes among experts was low. Attitude toward local industry seemed associated with, if not a cause of, attitudes about ranges of risk estimates. These reactions by industry neighbors appear to replicate the findings of Johnson and Slovic (1995, 1998), despite the hypothetical producer of risk estimates being industry instead of government. Respondents were older and less educated on average than were the earlier samples, but more diverse. Regression analyses suggested attitude toward industry was a major factor in these reactions, although other explanations (e.g., level of scientific understanding independent of general education) were not tested in this study.