Traffic fatalities, Peltzman's model, and directed graphs

We show how statistical methods based on directed graphs may be useful in modeling traffic fatalities by comparing models specified using directed graphs to a model originally developed by Peltzman. The comparison uses Peltzman's original data, as well as up-dated data (and coefficients) through 1993. Out-of-sample forecasts of traffic fatalities from Peltzman's model are compared with those from a model constructed using directed graphs over data for the more recent period. The directed graphs model outperforms Peltzman's model in root mean squared forecast error.