SAFETY INVESTMENTS AND OPERATING CONDITIONS: DETERMINANTS OF ACCIDENT PASSENGER-VESSEL DAMAGE COST

Econometric transportation safety research heretofore has focused on the likelihood of the occurrence of "safety related events" (event probability), e.g., investigating determinants of accident rates.' However, the risk of travel to the passenger (i.e., the probability of sustaining injury or death) not only has the aspect of event probability but also the aspect of severity conditional probability-the severity of the event given that it has occurred.2 Hence, an alternative (to event probability) for investigating the risk of travel is to focus on the severity of "safety related events." Since the severity of a "safety related event" is conditioned upon the occurrence of the event, the event and severity conditional probabilities of "safety related events" are expected to have common determinants.