A utility maximization model of driver traffic safety behavior. Accident Analysis and Prevention

Abstract-A simple utility maximization model is presented to illustrate that risk compensation is a natural part of human behavior when individuals pursue multiple goals with limited resources. In this positive economic model driver safety effort is determined by a balance between reduced risk and increased disutility cost. Changes which affect the balance induce drivers to change their own safety efforts. Under plausible conditions a change in exogenous safety, which is beyond driver control, causes a compensatory change in driver effort in the opposite direction. A sample of special seat belt use studies illustratively indicates the usefulness of the model. In keeping with the scientific spirit of recent inquiry I present one formulation of risk compensation and some nonpolicy evidence which in my judgment indicates that this formulation is useful in understanding driver traffic safety behavior. The formulation has several predecessors most of which have generic roots in Becker’s [1965] pathbreaking work in household production economics. The essence of the utility maximization model of traffic safety behavior is that the driver has safety and nonsafety goals and that the driver has some control over safety. In this sense the model is similar to Wilde’s [1982] theory of risk homeostasis, but the model is different in that it focuses on the choice o