A DYNAMIC MODEL OF THE URBAN PROCESS

Spatial form evolves in a complex manner. The dynamic nature of the activities within an urban region makes the process of urban structure formation, here referred to as the "urban process", a dynamic one. In this report, the dynamics of the various components of the process, and the interactions among the components, are examined and deductively represented to obtain a large-scale model framework of the urban process. Specifically, three major functional components are modeled: (1) Trip Behavior, where the trip taking (both, for work and non-work trips) behavior is modeled, (2) Residential Locational Decisions, residential choices and movement of workers are conceptualized, and (3) Service Locational Decisions, where the normative decision-making of entrepreneurs and agencies is represented. Applications with a preliminary implementation of the model illustrates the feasibility and the importance of modeling the dynamics and transients in the urban process for policy analyses. Applications also indicate some prevalent nonlinearities in the process. As indicated in the report, the model framework appears promising and points out research directions for the eventual development of a dynamic transportation/land-use planning model.