The role of volume-delay functions in forecasting and evaluating congestion charging schemes: the Stockholm case
2015 (English)In: Transportation planning and technology (Print), ISSN 0308-1060, E-ISSN 1029-0354, Vol. 38, no 6, 684-707 p.Article in journal (Refereed) Published
This paper uses observations from before and during the Stockkholm congestion charging trial in order to validate and improve a transportation model for Stockholm. The model overestimates the impact of the charges on traffic volumes while at the same time it substantially underestimates the impact on travel times. These forecast errors lead to considerable underestimation of economic benefits which are dominated by travel time savings. The source of error lies in the static assignment that is used in the model. Making the volume-delay functions (VDFs) steeper only marginally improves the quality of forecast but strongly impacts the result of benefit calculations. We therefore conclude that the dynamic assignment is crucial for an informed decision on introducing measures aimed at relieving congestion. However, in the absence of such a calibrated dynamic model for a city, we recommend that at least a sensitivity analysis with respect to the slope of VDFs is performed.
Place, publisher, year, edition, pages
2015. Vol. 38, no 6, 684-707 p.
congestion charging, transport model, volume-delay functions, cost-benefit analysis, Stockholm
Transport Systems and Logistics
IdentifiersURN: urn:nbn:se:kth:diva-173261DOI: 10.1080/03081060.2015.1048948ISI: 000359699600006ScopusID: 2-s2.0-84938421005OAI: oai:DiVA.org:kth-173261DiVA: diva2:852607
QC 201509092015-09-092015-09-092015-09-09Bibliographically approved