University of California Transportation Center

One of the challenges facing intermodal integration is that the planning framework needed for it lacks appropriate measures of level of service that cut across the modes involved and the connections between them. In this study we develop a framework and a set of metrics of level of service in a multimodal context. We propose a conceptual framework in which we identify the various attributes of level of service and the method of their integration. These measures of performance are defined from two perspectives: the user’s perspective (the demand side) and the provider’s perspective (the supply side). An analytical framework is then proposed in which a working definition of a “multi-modal corridor” is adopted and a methodology for defining and combining measures of performance for such a corridor is developed. The methodology is defined in the context of evaluation for the purpose of choosing among alternative corridors. The approach is grounded in utility theory and quantitatively these measures of performance are defined as indirect utility functions of the type used in choice models. In combining the measures of performance for different elements of a multi-modal corridor, the methodology recognizes that some are additive, either simply or with appropriate weights, while others are not additive at all and exhibit phenomena such as weakest link, or maximal effort. Safety is a good example of this. The basic proposition is that many level of service metrics are non-additive and their combination for a multimodal systems requires specific models that reflect the way the attributes impact users of different modes and during different segments of a multimodal journey. This study concludes by recommending some research directions to develop the models needed for the integration of level of service measures for multi-modal corridors and for their inclusion in indirect utility function.