Environment and Planning B: Urban Analytics and City Science

Some of the methodological problems that have arisen in the course of recent research in planning processes are considered with a view to providing would-be researchers with some general guidelines to help them in designing research strategies. With this essentially practical objective in mind, these problems are grouped into four broad categories for discussion purposes. These concern the question of general theoretical perspectives, the need for more precise statements regarding the nature of planning processes, the implications that follow from the adoption of a case study approach, and the need to devise a simple classification scheme which can be used to identify priority areas for future research, respectively.

Human beings are not very good at making decisions or planning. It is argued that a major reason for this lies in the essential logic that underlies decisionmaking discourse. Those with experience of decisionmaking will know that wild speculations and conflicting values confound the process, quite apart from logical confusions or mixing the general with the particular. This paper, the first of two, introduces a simple now-future logic which makes the concept of speculation well-defined. It is shown that speculations infect discourse with uncertainty out of all proportion to their frequency of occurrence. A ‘normative logic’ is introduced which allows arguments to be evaluated in terms of mixtures of good-bad-true-false. Decisions are sets of stated actions or intentions which are consistent with decision constraints as agreed by the decisiontakers. Decisionmaking authority is hierarchical and this is discussed in the context of the related, but distinct, hierarchy of set-theoretic aggregation of the particular into the general. Sixteen guidelines for decisionmakers are stated in terms of the structures defined. The forthcoming paper, which complements this, gives an extension of the ideas simply treated here with a discussion of strategic planning in terms of social time structurally defined as p-events.

In this paper, methods originally developed by Saaty for modelling the importance of attitudes concerning particular issues are applied to a set of attitudinal data associated with the views of a group of experts on the development of urban systems analysis and modelling. Saaty's model is first described, with emphasis on the technique for recovering the importance or weight of issues from pairwise comparisons of the same issues, and with a demonstration of how manageable comparisons can be handled by decomposing a large set of issues hierarchically. These notions were used to structure the collection of attitudinal data from a group of experts involved in assessing the state of their art at a NATO Advanced Research Institute on Systems Analysis in Urban Policy-Making and Planning held at Oxford in the late summer of 1980. The model is adapted to these data and extended to encompass the idea of an ‘average’ set of attitudes through the construction of an average hierarchy from the individual attitudinal hierarchies. The ideas are then applied to the respondents' data. First a partial analysis of the twenty-four responses received is presented, and then a fuller analysis based on the notion of the average hierarchy is described for sixteen of these responses. A large measure of consensus with respect to the importance of different areas of urban systems analysis and modelling and the factors posing the greatest problems is apparent. From the analysis, several directions for future research both of a substantive and of a methodological nature are indicated.

Conventional multivariate statistical techniques are inhibiting in their analysis of structure. This paper introduces the ‘language structure’ or ‘Q-analysis’ proposed by R H Atkin, and compares its results with widely adopted multivariate statistical techniques within the context of the socioeconomic structure of towns in England and Wales.

This study deals with the development and application of a methodology which permits optimal planning of an urban streetlighting system. It presents for the first time—to the best of the authors' knowledge—a procedure for the quantitative estimation of the utility accruing from street-lighting. The multivariable utility function divided by the installation cost of lighting for each street yields an efficiency coefficient for a given lighting project. The rank order of these coefficients, listed in descending order, shows the marginal utility of each project realized.

An optimization model based on an integer programming algorithm was employed because it permits periodical (for example, annual) selection of a set of indivisible projects to be realized during a given period so as to derive maximum economic and social utility, subject to budgetary and technological constraints.

The first part of the methodological derivation yields the utility function of the lighting system for each street. The components of the function, some of which represent subjective assessments, were identified by the Delphi method, which permits derivation of subjective values for groups of interviewees whose assessments may reasonably be assumed to be crucial in determining the relative values of the objectives used in the utility function.

The optimization process was carried out using the IBM MPS X (an integer programming algorithm). The selection process was extended and deepened so as to render it sensitive to benefit from economies of scale and external economies. The conventional practice, whereby residents have no say in the planning of the lighting system in their city, was abandoned. Residents' value judgements concerning the relative importance of the objectives to be served by the lighting system were incorporated into the planning process.

A new paradigm involving evolution and change through the concept of dissipative structures has been developed in recent years in the physical sciences. This paradigm has profound implications for prediction, for design, and for models which purport to explain how complex systems develop. The potential of these ideas is illustrated by showing how the concept of evolution through bifurcation can be used to explain the development of form. Particular reference is made to origami, which clearly shows how the new theory involves qualitative rather than quantitative change. These ideas are further illustrated through models of the evolution of microeconomic markets and urban systems.