This study derives the implied values of reducing the risks of fatal and non-fatal injuries for different road user populations. Values are obtained for “typical” adults, children (as implied by their parents’ actions) and adults who ride motorcycles. Also considered is whether individuals evaluate small time increments consistently with larger time allocations.
Topic: 25. Time Valuation
A minute saved on a journey cannot normally be used to earn extra money. Therefore in mode choice models the wage rate should be replaced by the expenditure rate (purchasing power per unit of time available to spend it), based on per capita family income.
Firms using the Humber bridge regularly for goods transport were able to benefit in a number of ways, and in this case it is appropriate to value savings in drivers’ time by the wage rate. But this conclusion may not be applicable to the more usual case of smaller incremental road improvements.
Modal split may vary from day to day, and uncertainty is an important element in the commuter’s choice.
Direct experiment is a new way of valuing time savings. The authors asked people to grade various combinations of walk, wait and invehicle time. They assess the usefulness of the method and possible improvements.
A comment on the article published in this Journal in May 1976 and later contributions in 1978, with the author’s rejoinder.
A multinomial logit model was found satisfactory for estimating values for time for business and non-business travel in Greece. The author suggests that similar studies for other developing countries would be useful.
Valuations of travel time for cost-benefit studies should not be based exclusively on individual values or on the wage rate, but should combine both, with allowance for taxation. But individual values should continue to be used for modal choice models.