Unifying Long- and Short-Distance Personal Travel in a Statewide Planning Model

A disaggregate behavioral tour-based microsimulation model was developed to forecast intrastate long-distance personal travel on a typical weekday as part of an overall statewide travel model system for all residents of California. A novel approach to what is traditionally described as travel generation was developed as a series of choice models focusing on consistency and integration with other components of the model system. Key features include the explicit integration of this long-distance personal travel model with the complementary short-distance personal travel model, the specification of a travel party size model for long-distance travel based on household size, and the development of models to represent characteristics of the long-distance travel tour, including duration of tour (number of nights), travel day status for a typical weekday, and time of travel within the weekday. The explicit trade-off between long- and short-distance travel produces appropriate sensitivities and reproduces the real-world phenomenon of rural travelers producing more long-distance travel. Subsequent models not described in detail in this paper take advantage of this information; in particular, party size has a significant effect on mode choice. The model system is operational and has been calibrated and validated.