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Incorporating crowding into the San Francisco activity-based travel model


Information produced by travel demand models plays a large role decision making in many metropolitan areas, and San Francisco is no exception. Being a transit first city, one of the most common uses for San Francisco’s travel model SF-CHAMP is to analyze transit demand under various circumstances. SF-CHAMP v 4.1 (Harold) is able to capture the effects of several aspects of transit provision including headways, stop placement, and travel time. However, unlike how auto level of service in a user equilibrium traffic assignment is responsive to roadway capacity, SF-CHAMP Harold is unable to capture any benefit related to capacity expansion, crowding’s effect on travel time nor or any of the real-life true capacity limitations. The failure to represent these elements of transit travel has led to significant discrepancies between model estimates and actual ridership. Additionally it does not allow decision-makers to test the effects of policies or investments that increase the capacity of a given transit service. This paper presents the framework adopted into a more recent version of SF-CHAMP (Fury) to represent transit capacity and crowding within the constraints of our current modeling software.

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Zabe Bent, Rachel Hiatt, Jesse Koehler, and Billy Charlton at the San Francisco County Transportation Authority, Viktoriya Wise at the San Francisco Planning Department, and Julie Kirshbaum and Peter Straus at the San Francisco Municipal Transportation Agency.

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Correspondence to Elizabeth Sall.

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Zorn, L., Sall, E. & Wu, D. Incorporating crowding into the San Francisco activity-based travel model. Transportation 39, 755–771 (2012).

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  • Transportation planning
  • Transit planning
  • Activity-based travel models
  • Transit crowding