This paper presents some results of research at the Transport Research Laboratory (TRL) about the relationship between the speed at which an individual driver chooses to drive and that driver's accident liability. 24 sites on a wide range of road types, but excluding motorways and highly trafficked urban centres, were selected. The road sections were long enough to enable the vehicles to have reached constant speeds. A postal questionnaire, about a wide range of factors likely to influence speed and accidents, was sent to 9453 drivers, of whom just over 5000 responded. The study showed that one unobtrusive measurement of vehicle speed on a public road can be used to measure behaviour objectively, and successfully linked to information about speed choice behaviour. Demographics, trip characteristics, and various psychological factors were all found to affect a driver's choice of speed significantly.
Abstract