[Excerpt] "Risk judgments seem related to which definitions of risk a person uses. Earlier studies suggest that people who use a "probability" definition of risk give different, and somewhat lower, subjective estimates of risk than those who instead prefer a "consequence" definition. In addition, an "optimistic bias" often can be found, and subjects usually evaluate personal risk systematically lower than risk for people in general."
Pål Ø.U. Dåstol & Britt-Marie Drottz-Sjöberg, Varied Definitions of Risk Related to Sensation Seeking Trait, 11 RISK 197 (2000).