Intersection accident frequencies

The percentage distribution of intersection accident frequencies for accidents between vehicles from adjacent approaches at an intersection appears to be constant over long periods of time. The work reported here also shows that the negative binomial distribution was unsuited, but the observed distribution was well described by the logarithmic series distribution (LSD). The LSD has the advantage of having only one parameter which is determined from the mean number of accidents per intersection. Testing showed that the level of agreement between the observed data and the predicted values was at least 0.99. Subdividing the intersections according to road class showed that the distribution of intersection accident frequencies was still well described by the logarithmic series.