Detection and analysis of accident black spots with even small accident figures.

Accident black spots are usually defined as road locations with high accident potentials. In order to detect such hazardous locations we have to know the probability of an accident for a traffic situation of some kind, or the mean number of accidents for some unit of time. In almost all procedures known to us, the various road locations are treated as isolated spots. With small accident figures it is difficult to detect such places in the known procedures. An alternative procedure starts from the comparison of the locations with each other. The central question is: what do accident black spots have in common and in which respects do they differ other than in location. To answer this question we have to relate the accident figures to the road and traffic characteristics of the locations. The classification of locations is based on the characteristics of the locations. A canonical score is computed for each location from the road and traffic characteristics of the locations. This score may be transformed into the probability of an accident. Given the accident reduction effect of some countermeasures, the expected number of accidents after reconstruction can be predicted. For the covering abstract of the conference see IRRD abstract no 264967.