A survey has shown that public perceptions of comparative risks differ radically from the assessments of risk-management experts. For example, living near a nuclear power plant was judged a much greater risk by the survey respondents than it was by the experts. On the other hand, exposure to X-rays was judged a significantly lower risk by the survey respondents than it was by the experts. Psychologists have found that people tend to be more worried about risks they consider involuntary than about risks they consider voluntary. Thus the survey results were probably caused by the respondents' tendency to consider involuntary risks to be greater than they actually are.
The assumption that the survey's respondents did not include people living near nuclear power plants is required by the argument.