Environment and Planning B: Urban Analytics and City Science

Land-use strategies such as city compaction are the basis for creating livable communities with more accessible land-use patterns that reduce automobile dependency. In previous studies the various advantages of the compact city have been proven, especially from environmental perspectives, but there still remain major questions, such as how the compact city can be induced and whether it can bring a higher quality of life. The authors' main objective in this paper is to answer these questions by using a multiagent land-use transport model to represent the interaction of agents' locations, the effects of mixed land use, and the agglomeration merits or demerits of agents. This model is used to examine the effectiveness of policy measures aimed at achieving a compact city from the viewpoint of urban physical compactness, total trip length, energy consumption, and the social welfare of residents.

The utilization of multiagent technology for urban planning purposes has already received much attention with regard to predicting and evaluating the effects of different policy scenarios and plan alternatives. The generation of these plan alternatives, however, remains underexplored in this context. In this paper the authors describe a multiagent model for generating alternative land-use plans, in which the agents are land-use experts that initiate the development of plan proposals and communicate with each other over time in order to draw up the proposals incrementally. The authors present a probabilistic approach to agent behaviour to enable decisionmaking under conditions of uncertainty. They describe what personal and collective beliefs agents construct and use in order to choose their actions strategically. The negotiation, taking place between the initiating agent and the other agents, aimed at reaching agreement with regard to the various claims, is organized as an iterative process in which both parties consider conciliatory adjustments to their strategies, and thus their decisions, in order to try to find mutually acceptable solutions. A hypothetical case study demonstrates the operation of the model and the effects of its behavioural parameters.

Planning-support systems offer an effective way of integrating social, economic, and environmental datasets, enabling a number of holistic spatial planning scenarios to be generated and evaluated by local planners. With increased acceptance of computer technology as a platform for the development and delivery of professional tools, planning-support systems (PSSs) may well be embraced by practitioners to improve current practices, just as computer-aided design (CAD) has been widely accepted by architects as a useful design and visualisation tool. There is some perceived optimism, (or realism?) that this may be the case sooner rather than later. It is believed that ‘What if?’ is one such PSS which is suitable for enhancing current planning practice. The author provides a technical and experiential examination of an application of the What if? PSS in assisting in the formulation of a sustainable land use strategy for Hervey Bay, Australia, supplementing previous published results. The focus of the research is to examine the underlying model and discuss the collaborative application of the PSS with local planners in a scenario-building exercise. Furthermore, the perceived strengths and weaknesses of the PSS are outlined from the perspective of the urban modeller, together with ex-ante feedback from the local planners on the use of the PSS to formulate urban-growth scenarios. In conclusion, the merits of the use of such a PSS are discussed and some future directions for the development of collaborative spatial decision-support tools are offered.

A number of shortcomings of space syntax—a well-known technique of urban analysis—were recently discussed in the scientific literature. They are mostly traceable to the reliance in space syntax on the ‘axial map’: a simplified line-of-sight description of the city, which is then analysed based on its topology. This paper explores how another type of urban representations—namely the urban digital elevation model (DEM), a raster map which stores building heights—could prove helpful in providing complementary information to space syntax. Although the use of DEMs is common in the geo-sciences, their application in urban studies is more recent and shows promise. This paper presents several analysis algorithms to derive urban lines of sight, viewsheds, travelling time maps, and simulations based on cellular automata. The relevance of the approach is discussed, suggesting that it could effectively complement traditional space syntax in the coming years.

In this paper we discuss the application of Ramblas to estimate the impact of three possible urban development scenarios in North Wing of the Randstad region in the Netherlands. These land-use scenarios concern the location of dwellings, office buildings, and industrial sites in Amsterdam and its surroundings. The three proposed scenarios differ mainly in terms of the degree of concentration, density of residential development, and the timing of the construction. Ramblas was applied to assess the impact of these scenarios in terms of sustainability criteria such as the number of kilometres travelled. The results suggest that global criteria are not enough to decide whether one scenario is preferable to another. Ramblas can provide more inside information.

Data on the shape of land lots are needed in urban planning analyses. However, large amounts of shape data are often unavailable. In this paper we develop a method of estimating the boundary lines of land lots. With the assumption that the vertices of lots are tentatively given and that their deviations from true positions follow certain kinds of probability distributions, the problem is formulated as an optimization problem of adjusting the positions of tentatively given vertices, subject to the constraints of available information such as lot size and frontage. In this problem, two objectives are considered: one is to maximize the log-likelihood function and the other is to minimize distortion of lot shape. An index called the ‘suitability degree’, based on the concept of fuzzy logic, is proposed for evaluating the quality of estimates and is used as a decisionmaking rule for determining the weight parameter in the objective function. The proposed method is empirically tested with real lots and the results are satisfactory. It reveals the feasibility of applying this method in urban planning.

Using plans and regulations when making decisions about urban development requires access to the many plans and regulations of many different organizations, both private and public. Current information technologies, the Internet and the World Wide Web in particular, make access to data from such disparate sources feasible. Using these technologies to implement a ‘system of plans’ approach to urban development planning will, however, require a widely shared data model for structuring the content and meanings of plans and regulations and a widely shared language, based on this data model. This paper presents an initial version of a planning data model (PDM), several use cases that set the scope of such a data model, and illustrations of how the current version of the PDM supports these use cases. Further work can build on this data model, including an XML (extensible Markup Language) implementation for sharing the information. These tools will enable urban development decisionmakers to conceive of planning as involving many actors whose many plans can provide useful and usable information.

The urban park is a place where urbanites can escape from the stresses of everyday life. Using a set of fifteen photographs as visual stimuli, we attempted to identify those scenes that are liked by visitors to Kowloon Park, Hong Kong. The visual quality of an urban park scene is measured by its likeability, referring to the probability that the scene will evoke a strong and positive response among the users of the park. Because Hong Kong is an international metropolis, the respondent sample included both Hong Kong residents and tourists. The principal component analysis revealed the three underlying ‘dimensions’ of the appraisal aspects of the data: the ‘affective’ component, the ‘management status’, and the ‘naturalness’ of the scene. The results replicated the affective responses of park visitors toward the scenic aspects of urban park spaces, in which scenic beauty can be used as a proxy for acceptable management. Overall, the study has yielded useful information for park professionals to provide enjoyable urban park spaces in metropolitan areas to meet the needs of their citizens and visitors.