Explanatory factors of distorted perceptions of travel time in tram

This study has two aims. The first is to research the factors that influence deviations in perceptions of travel time with respect to actual travel time by analyzing distorted perceptions of travel time in tram. The second aim is to find out whether these explanatory factors are different for the two segments of users according to the sign of errors in their travel time perceptions, i.e. those who overperceive and those who underperceive travel time.This work is based on an internet survey carried out on students from the University of La Laguna, Spain, in May 2009, using revealed preference data. Several linear regression models were estimated using the backward elimination method of selecting variables. The variable called “perception error rate” is proposed as a measure of distorted perceptions of in-vehicle travel time and is explained as a function of actual in-vehicle travel time and a series of other novel variables, such as the perception of other travel time components (access, waiting, egress), as well as certain characteristics of the trip and traveler. The results obtained provide evidence that some of the variables that explain the distorted perceptions of travelers are different between the overperceiving and underperceiving samples. This finding shows that estimating just one model with a total sample could lead to erroneous conclusions. Since travelers make decisions based on their perceived travel times, transport policy should focus on overperceiving travelers, and specifically on those who travel frequently. According to our results, policies should be aimed at facilitating access to stops, increasing frequency of service to reduce waiting time and decreasing the relative advantages associated with the use of private vehicles. This last point is because travelers overperceive travel time by tram more when accessing tram stops by car.