Driver behaviour during flashing green before amber: a comparative study.

The paper discusses the results of extensive measurements of drivers' stopping behaviour during signal programmes with and without flashing green before amber. Ten locations in Switzerland, Austria, and Germany were recorded with a video camera and analysed using an image-processing system. About 5000 cycles were documented. The analysis shows that the flashing green increases the number of early stops, as drivers tend to underestimate the duration of the time to the end of amber. Discrete choice models of the stopping behaviour are estimated for inclusion in suitable microsimulation models of traffic flow. The model results show that speed and distance to stop line, and their interaction (potential time to the stop line with unchanged speed) explain the stopping process.