New Perspectives on Planning Support Systems

Abstract

As Hopkins (1999) points out, the idea of using computers to support planning is hardly new. Mainframe computers were applied to planning problems in the 1950s and 1960s in the Chicago Area Transportation Study and by the urban modelers of the 1960s and 1970s. The diffusion of 'microcomputers* in the 1980s and 1990s has made a whole range of computer-based tools and techniques-from spreadsheets and database managers to expert systems and GIS readily available to planners around the world. These developments have been followed closely in the pages of this journal since its inception a little over twenty-five years ago (Klosterman, 1998). Nevertheless there is a new excitement in the world of computer-based planning. This excitement is due in part to the continued steady increases in power, capacity, and speed and continually lower cost-of computer equipment. It also reflects the dramatically increased quantity and quality of spatially referenced information that is becoming available with the maturation of municipal and regional GIS databases, the incredible growth of the Internet, and the emergence of new tools and techniques such as artificial neural networks and cellular automata that could not even be imagined a few years ago. More fundamentally, the renewed interest in computer-based planning reflects the emergence of new conceptions of the role which computers can play in planning research and practice. These new conceptions arc increasingly known under the label of planning support systems (PSS), a term first used in print by Harris fully ten years ago (Harris, 1989). PSS began in response to planners' fascination with GIS as a reminder that geographically referenced information and spatial analysis techniques alone cannot adequately support all of planning (Harris, 1989; Harris and Batty, 1993). It has matured into a conception of integrated systems of information and software which bring the three components of traditional decision support systems-information, models, and visualization-into the public realm (Batty, 1995; Klosterman, 1997). PSS information includes not only spatially referenced information stored in a GIS, but also small-area statistical data and information stored in other media such as text and graphic images. PSS models include planners' familiar tools for conducting analysis, projecting future conditions, and modeling spatial interaction and new tools such as expert systems and artificial neural networks. And PSS visualization includes not only planners' traditional charts, graphs, and maps but also three-dimensional simulations and multimedia text, video, and sound. Supporting all three components are new and richer images of the role which computer-based tools such as PSS can play in public policymaking and collaborative decisionmaking. The papers in this theme issue provide new and provocative perspectives on the rapidly emerging field of PSS. In his paper Harris (1999) considers fundamental questions of how our computational approaches can be modified to deal better with the imperatives of contemporary planning practice. He begins by considering the characteristics of contemporary urban development and identifying three major professional activities in planning: (1) analysis, the deployment of knowledge; (2) design, the activity of invention; and (3) public participation, the engagement of planning with its clients and publics. Drawing on the work of Healey, Innes, and other 'communication theorists', he identifies new roles for public participation, arguing that the public soon will-and