The national and international literature on reliability of travel times in passenger and freight transport has been reviewed to obtain insight into the definitions that are used, the monetary values that have been obtained and the methods that have been used for this. Furthermore, the issue whether these values could be applied in cost-benefit analysis, especially in the framework used in The Netherlands, was investigated. In total, 40 reports and articles were studied and summarised in this review. No monetary values for reliability and other aspects of quality were found that are used in official national cost-benefit analyses. But this issue is being investigated in some countries (besides in the Netherlands also in the United Kingdom and Sweden), and studies have been carried out in several countries that yield values in money units or time units for the reliability of travel times. Representative money values for The Netherlands, especially for car traffic, are lacking. All the studies on the value of reliability that were reviewed yield that this is a factor of substantial importance: none of the studies reviewed concluded that this factor can be neglected. For freight transport in The Netherlands and for public transport, Dutch valuation studies have been carried out in recent years, with their own, specific definitions of reliability of transport time. (Author/publisher)
Samenvatting