A COMPARISON OF ACCIDENT RATES USING THE LIKELIHOOD RATIO TESTING TECHNIQUE

Comparing transportation facilities (i.e., intersections and road sect ions) in terms of traffic accident occurrences is among the interests of most traffic safety analysts. This paper uses statistical technique s as appropriate tools for performing such analyses. Traditionally, tr affic accidents arc represented as occurrences of events per certain u nit, such as time and vehicle miles; this representation is consistent with Poisson nature. In this paper, Poisson distribution is used to d escribe the distribution of traffic accident occurrences. The objectiv e is to develop a test statistic in order to enable traffic analysts t o compare traffic accident rates in various transportation facilities. The obtained test statistic is simple and requires minimal data to pe rform the comparison analysis.