Samenvatting
This paper reports the use of variation tree analysis (VTA) to discover the human factors likely to cause accidents at unsignalised junctions. VTA uses a set of symbols within a flowchart-type pattern to enable analysis of a situation. Variation factors are deviations from normal safe driving behaviour. VTA was used to analyse a hundred and fourteen accidents from Japanese roads. The most numerous factors were maintaining speed on entry to the junction and failing to look for other drivers crossing the path of travel. Ten patterns of accidents were identified, most accidents being applicable to six patterns; details are given of these, with some of the VTA diagrams. For the covering abstract see ITRD E113725 (C 22328 CD-ROM).