Urban modeling and contemporary planning theory: Is there a common ground

Large-scale urban modeling seems to have finally come of age. Recent articles in the planning journals indicate a resurgence of interest in these models. ' Judging from the symposium on large-scale urban models in the 1994 winter issue of the Journal ofthe American PlanningAssociation, the renewed optimism about such models seems to stem from two sources: (a) the power of the now ubiquitous per-sonal computers and (b) the promise of geographic information systems (GIS) as an interactive communicative platform for testing and applying urban models. Pres-ently, almost every reported modeling effort uses GIS either as a final display of spatially disaggregated data or as inputs to the modeling process at various points in the model sequence. There is, however, a danger in succumbing to the euphoria of this rejuvenation of urban modeling. Although Douglass Lee's "Requiem for Large-Scale Models" (1973) is often quoted as the death knell for the first generation of large-scale urban models, a critical review of the history of modeling in North America unravels some more fundamental issues that militated against the incorporation of urban model