The delay costs of traffic disruptions and congestion and the value of travel time reliability are typically evaluated using single trip scheduling models, which treat the trip in isolation of previous and subsequent trips and activities. In practice, however, when activity scheduling to some extent is flexible, the impact of delay on one trip will depend on the actual and predicted travel time on itself as well as other trips, which is important to consider for long-lasting disturbances and when assessing the value of travel information. In this paper we extend the single trip approach into a two trips chain and activity scheduling model. Preferences are represented as marginal activity utility functions that take scheduling flexibility into account. We analytically derive trip timing optimality conditions, the value of travel time and schedule adjustments in response to travel time increases. We show how the single trip models are special cases of the present model and can be generalized to a setting with trip chains and flexible scheduling. We investigate numerically how the delay cost depends on the delay duration and its distribution on different trips during the day, the accuracy of delay prediction and travel information, and the scheduling flexibility of work hours. The extension of the model framework to more complex schedules is discussed.
Bibliographical noteFunding Information:
The paper has benefited greatly from comments and suggestions by three anonymous referees. We would also like to thank Marcus Sundberg for helpful comments on an early version of the paper. The work of the first two authors was supported by the Swedish Road Administration and the Swedish Governmental Agency for Innovation Systems (Vinnova). The work of the third author was supported by the National Science Foundation under Grant No. 0825768: BRIDGE: Behavioral Response to the I-35W Disruption: Gauging Equilibration.
Copyright 2017 Elsevier B.V., All rights reserved.
- Delay cost
- Value of time