Semi‐dynamic traffic assignment model with mode and route choices under stochastic travel times

SUMMARY Transportation network conditions vary significantly during the course of a day. In many urban areas, public transit and (private) automobiles constitute the actual forms of transportation that use such networks. Public transportation by rail is more reliable than by automobiles or buses; therefore, ordinary static and deterministic traffic assignment models with combined mode and route choices may not be suitable to assess a transportation network that includes public railways. Moreover, within‐day dynamics and reliability need to be incorporated in such a model. In this paper, we use a semi‐dynamic traffic assignment model that considers within‐day dynamics by improving the static traffic assignment model. In addition, stochastic travel times are incorporated into the model. Thus, we propose a semi‐dynamic traffic assignment model with mode choice between public transit and automobiles, route choice with stochastic travel times, and an accompanying computing algorithm. This model enables us to assess within‐day dynamics of transportation networks and travel time reliability of public railways. Copyright © 2012 John Wiley & Sons, Ltd.