Overreporting vs. Overreacting : Commuters' Perceptions of Travel Times

Participants of a large-scale, real-life peak avoidance experiment have been asked to provide estimates of their average in-vehicle travel times for their morning commute. Comparing these reported travel times to the corresponding actual travel times, we find that travel times are overstated by a factor of 1.5 on average. We test to which extent driver- and link-specific characteristics explain the overstating. Subsequently, we investigate whether the driver-specific reporting errors are consistent with the drivers' scheduling behavior in reality as well as in hypothetical choice experiments. For neither case, we find robust evidence that drivers behave as if they misperceived travel times to a similar extent as they misreported them. These results imply that reported travel times are neither an appropriate measure for representing actual nor perceived travel times, and are thus a strong caveat against the uncritical use of reported travel time data in research and policy