Change search
ReferencesLink to record
Permanent link

Direct link
Inter-temporal variation in the travel time and travel cost parameters of transport models
2012 (English)Report (Other academic)
Abstract [en]

The parameters for travel time and travel cost are central in travel demand forecasting models. Since valuation of infrastructure investments requires prediction of travel demand for future evaluation years, inter-temporal variation of the travel time and travel cost parameters is a key issue in forecasting. Using two identical stated choice experiments conducted among Swedish drivers with an interval of 13 years, 1994 and 2007, this paper estimates the inter-temporal variation in travel time and cost parameters. It is found that the travel time parameter has remained constant over time but that the travel cost parameter has declined in real terms. The trend decline in the cost parameter can be entirely explained by higher average income level in the 2007 sample compared to the 1994 sample. The results support the recommendation to keep the travel time parameter constant over time in forecast models but to deflate the travel cost parameter according to forecasts of income increases among travellers and the relevant income elasticity of the cost parameter. Evidence from this study further suggests that the inter-temporal and the cross-sectional income elasticity of the cost parameter are equal. The average elasticity is found to be -0.8- -0.9 in the present sample of drivers, and the elasticity is found to increases with real income level, both in the cross-section and over time.

Place, publisher, year, edition, pages
Stockholm: Centre for Transport Studies Stockholm, Swedish National Road & Transport Research Institute (VTI), KTH Royal Institute of Technology, S-WoPEc, Scandinavian Working Papers in Economics , 2012. , 22 p.
CTS Working Paper, 2012:16
Keyword [en]
Journey time, Cost, Demand (econ), Forecast, Mathematical model, Variability, Trend (stat), Stated preference, Income
National Category
Transport Systems and Logistics
Research subject
Road: General works, surveys, comprehensive works, Road: Economics; Road: Transport, society, policy and planning, Road: Personal transport
URN: urn:nbn:se:vti:diva-670OAI: diva2:669365
Available from: 2013-12-03 Created: 2013-12-03 Last updated: 2014-03-18Bibliographically approved

Open Access in DiVA

fulltext(391 kB)150 downloads
File information
File name FULLTEXT01.pdfFile size 391 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Transport Systems and Logistics

Search outside of DiVA

GoogleGoogle Scholar
Total: 150 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 19 hits
ReferencesLink to record
Permanent link

Direct link