FROM THE SINGLE LINE MODEL TO THE SPATIAL STRUCTURE OF TRANSIT SERVICES : CORRIDORS OR DIRECT?

The microeconomic analysis of public transportation involves the optimisation of all resources, both users'and operators'. This has been applied to optimise frequency and fleet size for isolated transit lines, as well as to study optimal spacing for multiple lines serving a single destination. In this paper the spatial structure of transit services is analysed within the context of multiple origins and destinations. Direct services (no transfers) are compared against transit corridors for simple though illustrative spatially diversified demands. The best transit structure is shown to depend upon the demand volume, the relative time values and on network related parameters. Optimal fleet size preserves the "square root rule". © The London School of Economics and the University of Bath 2003