Abstract:
Comparisons using raw fatality rates (per vehicle miles traveled or per population, or both) are likely to lead to biased pictures of relative traffic safety in the states. This study attempts to provide better pictures for a state-by-state comparison by using random intercept models based on the state-level panel data from 2000 through 2004. The data include demographic economic characteristics and roadway characteristics of 46 U.S. states. Predicted fatality rates were computed with the estimated models and fixed factors tuned to the values for Virginia as a reference. New rankings were generated on the basis of predicted rates and compared with raw rankings based on the raw rates. About half of the top 10 safest states in the raw rankings dropped out of the top 10 in the new rankings, which took into account control factors. However, the uncertainty of the estimated random intercepts suggests that the new rankings can be varied considerably; this implies that the rankings should not be used as stable traffic safety yardsticks for comparison between states, although they are better than the raw rankings.
