Using prospect theory to investigate the low marginal value of travel time for small time changes

• Published in: Transportation research. Part B: methodological 2012-09, Vol.46 (8), p.917-932
• Main Authors: Hjorth, Katrine, Fosgerau, Mogens
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Ground, air and sea transportation, marine construction; Prospect theory; Small time savings; Stated preference data; Transportation planning, management and economics; Value of travel time
• ISSN: 0191-2615; 1879-2367; 1879-2367
• DOI: 10.1016/j.trb.2012.04.001

► We consider the problem of the low value of small time savings. ► Test if prospect theory can explain the phenomenon. ► Show how to design SP data to allow identification of the relevant parameters. A common finding in stated preference studies that measure the value of travel time (VTT) is that the measured VTT increases with the size of the time change considered, in conflict with standard neoclassical economic theory. We present a new test of a possible explanation for the phenomenon that builds on the diminishing or constant sensitivity of the value functions in prospect theory. We use stated preference data with trade-offs between travel time and money that provide separate identification of the degrees of diminishing sensitivity for time and money gains and losses. This enables us to test and potentially falsify the prospect theory explanation. We conclude that prospect theory remains a potential explanation of the phenomenon.