It is well known that the accident liabilities of drivers fall with age and with increasing driving experience. However, quantifying the changes in accident liabilities as a result of maturation (the age effect) as distinct from that of increasing driving experience (defined here as the number of years a driver has been driving since passing the test) has always been difficult. In statistical terms, the difficulty arises from the fact that in any large random sample of drivers, age and experience are highly correlated and therefore difficult to disaggregate. Estimating these effects from national accident statistics is difficult for the practical reason that, whereas a driver’s age is usually collected with the official statistics, driving experience is not. However, if it is required to make estimates of the accident consequences of a range of policy options which might influence the age at which young drivers start driving, the quantification of the effects of age and experience on injury accidents is essential. This paper describes an attempt to calibrate an age-experience relationship obtained from a statistical accident liability study carried out some years ago, making use of nationally reported STATS19 injury accident data, driver licensing data from the Driver Vehicle Licensing Agency (DVLA), data on driving test passes from the Driving Standards Agency (DSA) and data on annual mileages from the National Travel Survey (NTS). (Author/publisher) For the covering abstract see ITRD E116881.
Abstract