Who Knows Where the Time Goes? A Response to David Metz

摘要

Metz (2008) points to an interesting phenomenon from which he draws the wrong conclusion. My argument is presented in the form of a series of assertions. People make travel choices based on some notion of the generalized cost of travel (McIntosh and Quarmby, 1970). There is room for debate about the components of generalized cost which ideally should include reliability and comfort as well as time and money, but for many choices, time and money will be the dominant elements of 'true' generalized cost. There is very strong evidence from the public transport literature as well as cases such as the London congestion charge and the M6 Toll that behaviour patterns imply that people are trading between time and money. So in cross sections of data involving choices between fast and slow trains or tolled and untolled roads, values of time varying by income, journey length, journey purpose, etc. can be inferred. Some versions of the constant travel time budget thesis imply that time is not tradeable for money. The evidence of hundreds of choice studies is to the contrary.