A methodology to derive the critical demand density for designing and operating feeder transit services

Document Type

Journal Article

Publication Date


Subject Area

planning - route design, land use - urban density, ridership - demand, mode - mass transit


Transit, Service design, Public transit, Operations, Methodology, Methodologies, Mass transit, Local transit, Fixed routes, Feeder services, Demand responsive transportation, Analytical models


Feeder lines are one of the most often used types of flexible transit services connecting a service area to a major transit network through a transfer point. They often switch operations between a demand responsive and a fixed-route policy. In designing and running such systems, the identification of the condition justifying the operating switch is often hard to properly evaluate. In this paper, the authors propose an analytical model and solution of the problem to assist decision makers and operators in their choice. By employing continuous approximations, the authors derive handy but powerful closed-form expressions to estimate the critical demand densities, representing the switching point between the competing operating policies. Based on the results of one-vehicle and two-vehicle operations for various scenarios, in comparison to values generated from simulation, the authors verify the validity of their analytical modeling approach.


Transportation Research Part B Home Page: http://www.sciencedirect.com/science/journal/01912615