The reliability of transportation systems and its influence on the choice behaviour: presentation at STRC 2002, 2nd Swiss Transport Research Conference, Monte Verità, Ascona, March 20-22, 2002

Our society and especially today's business life is structured by time-tight schedules.Time has been established as an expensive good.Transportation planning takes account of the time spent and its value.It is considered in the usual choice models such as destination-, route-or mode-choice models.These choice models calculate a utility for each alternative and choose the one which shows the highest utility.Currently time is included in the utility function, as either the mean trip duration or the mean speed of vehicles.But what is the utility of a fast car while it is standing in a traffic congestion?When people choose a mode to go somewhere they think not only about the normal duration of a trip but also about the reliability of the arrival time in the particular situation.Still the choice models mentioned generally do not contain a term concerning how reliable the alternatives are.One reason for not considering this item on the problem of how to measure and describe reliability for the users of transportation systems.This paper focuses on this problem.The measurement instrument was a SP-survey.It employed different methods of questioning as well as several types of presentation.The results of the survey were modelled by using the MNL approach.