INTEGRATED URBAN EVOLUTIONARY MODELING

Cellular automata models have proved rather popular as frameworks for simulatingthe physical growth of cities. Yet their brief history has been marked by a lack ofapplication to real policy contexts, notwithstanding their obvious relevance totopical problems such as urban sprawl. Traditional urban models which emphasizetransportation and demography continue to prevail despite their limitations insimulating realistic urban dynamics. To make progress, it is necessary to link CAmodels to these more traditional forms, focusing on the explicit simulation of thesocio-economic attributes of land use activities as well as spatial interaction. Thereare several ways of tackling this but all are based on integration using variousforms of strong and loose coupling which enable generically different models to beconnected. Such integration covers many different features of urban simulationfrom data and software integration to internet operation, from interposing demandwith the supply of urban land to enabling growth, location, and distributivemechanisms within such models to be reconciled. Here we will focus on developingbetter housing market and site subdivision processes within CA models, taking asour starting point the Dynamic Urban Evolutionary Model (DUEM) first proposed byXie (1994) and operationalized through a graphical user interface by Batty, Xie andSun (1999). We set our new model within a wider model-based infrastructure,devising a version which integrates the cellular approach to various residentialmodels of traditional form. We call the resulting system IDUEM. This model systemretains the cellular approach which is highly visual in terms of the way urbangrowth and change is conceived but uses this as the interface to different varietiesof model, making the framework much more applicable to real policy problems.