equipment on trains in the Nineteenth Century.

A reanalysis of his original data found numerous errors and his model failed to predict fatality rates before regulation. According to Peltzman, regulation was at best useless, at worst counterproductive. Peltzman found that the level of risk compensation in response to highway safety regulations was complete in the original study. But "Peltzman's theory does not predict the magnitude of risk compensatory behaviour." Substantial further empirical work has found that the effect exists in