Seat belt usage rates: a test of Peltzman's hypothesis.

Despite the universally accepted belief that the use of seat belts would have a significant impact upon the number of vehicular fatalities, current evidence indicates that relatively few drivers employ their seat belts. Various hypotheses have been offered to explain this phenomenon, many of which conclude that a driver's decision to use a seat belt is independent of the risk experienced in his trip making. This paper develops an economic model which focuses upon the relationship between driver use of seat belts and the travel conditions under which trips are made. Using data obtained from a national survey of households, a binary logit model is developed to test the hypothesis that seat belt usage is influenced by the level of risk experienced in one's trip making. The estimation results were consistent with the underlying hypothesis that individuals travelling in more risky environments are more likely to use their seat belts. The econometric results are then employed to examine various policy issues, including the predicted use of seat belts for population sub-groups, driver response to the introduction of a small urban car, and the impact upon the probability of a fatality resulting from vehicle fleet downsizing.