UC Irvine Institute of Transportation Studies

This paper describes the development of SIMAP, an activity-based microsimulation model for travel demand forecasting, and is part of a larger research effort aimed at the development of innovative transportation planning methodologies designed to address the limitations of current modeling practice in meeting current legislative and judicial mandates. The model builds upon existing research demonstrating that travel behavior should be viewed holistically using activity-travel patterns, a time-dependent representation of the activities and their attributes in which an individual engages. A microsimulation approach integrated with a geographic information system is advanced to synthesize individual, 24-hour activity-travel patterns for households that are reflective of the available transportation and land use system. By using activity-travel patterns as the basis of the SIMAP, the timing, sequencing, and connections between activities are explicitly included in the model where previously they would be disregarded. The final product of this research is  a prototype modeling system that has the potential to replace some or all aspects of the traditional 'four-step' modeling process. 

The next section describes the specifics of SIMAP. Section 3 presents a short discussion of the aggregate activity-travel pattern classification and results. Section 4 summarizes the implementation of the generation model, while Section 5 demonstrates a limited application of SIMAP. Finally, Section 6 concludes this paper by describing how this project's key contribution and suggests some extensions to the work.