A Generalized Bus System Cost Model

Because expanded and improved bus systems are potentially important for reducing automobile mileage and associated emissions, it is important to be able to estimate their costs. This generalized bus system cost model was developed for several applications in the San Diego Clean Air Project: (1) Used separately the model can estimate the annualized costs of providing a particular quantity and quality of bus service to a region, and can show the sensitivity of cost to changes in vehicles, service characteristics, load factor, system size, and the operating policies and institutional form of the bus operator. Because it requires only a small number of relatively gross design and policy descriptions as inputs rather than detailed engineering design specifications, the model can be used to examine the relationship between aggregate changes in the design and costs of a regional bus system. (2) The model is a component of an overall transportation model that evaluates the effect of changes in the transportation technology and management policies for auto, bus, and highway systems on the quantity, quality, and cost of transportation service.