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A new method for making interstate comparisons of highway fatality rates
1Injury Control Center, Harvard School of Public Health, Boston, MA 02115.
Abstract:
Highway fatality rates vary significantly among jurisdictions. Before attributing these variations to policy differences, it is important to account for exogenous factors (e.g. weather) that are beyond the control of policy makers. A new method is developed to identify states that are doing better or worse than expected. The method is applied to the 48 contiguous American states using highway fatality data for the years 1975 to 1986. A fixed effects linear model is used to estimate the fatality rate for each state, taking into account exogenous factors. Results indicate that many states have higher or lower fatality rates than is expected based on a ranking of states according to crude fatality rates. Policy implications are discussed.
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