New technology makes it possible to register driver behaviour during long periods in their everyday driving. In traffic safety research the focus of interest concerns behaviours that are dangerous for the drivers themselves or for others. It is well known that excessive speed increases risk of accident. However, when a lot of speed data is gathered over a long time, it is important to aggregate data in an optimal way with respect to risk of accident. In the present paper different aggregated measures of speed are discussed and this discussion is based on data collected during a two year ISA-study of drivers' speed behaviour. Different aggregations of speed data will be analysed and evaluated against questionnaire data collected before and under the ISA-project. For the covering abstract see ITRD E123193.
Abstract