Environment and Planning B: Urban Analytics and City Science

Privately owned public spaces are frequently criticized for diminishing the publicness of public space by restricting social interaction, constraining individual liberties, and excluding undesirable populations. This study empirically determines whether, as is commonly believed, privately owned public spaces are more controlled than publicly owned spaces. To frame our empirical work, we propose a conceptual model that identifies publicness as the interaction between the ownership, management, and uses/users of a space. We then examine the management dimension using an observation-based index to assess spatial management paradigms in publicly and privately owned spaces. We find that the use of the private sector to provide publicly accessible space leads to increased control over use, behavior, and access. Furthermore, while both publicly and privately owned public spaces tend equally to encourage public use and access, managers of privately owned spaces tend to employ more features that control behavior within those spaces. More specifically, spatial control in privately owned spaces is normally achieved through the use of surveillance and policing techniques as well as design measures that ‘code’ spaces as private. Important findings are presented for planners, policy makers, and others concerned with the future of publicly accessible spaces.

With the adoption of the European Landscape Convention the importance of landscape character and amenity functions have gained increased political recognition across Europe. Landscape complexity has been proposed as an important concept for describing visual character, with a range of landscape metrics developed for describing visual complexity. We present the results of a survey relating specific landscape metrics of complexity with preference for landscape. The survey used visualisations of six scenarios of landscape composition which showed differences in the amount of land cover as well as the distribution between open land use and forest. Metrics of complexity were applied for both map representation and panoramic scenes of the landscape. The relationship between complexity and preference was tested and strong relationships were found for the Shannon diversity index, Shannon evenness index, and aggregation index when applied to both maps and perspective views. The only background factor demonstrating a relationship with preference was age, whilst gender, occupation (ie working with landscape issues or not), and membership of an organisation involved with landscape issues all showed weaker relationships with preference.

The fringe-belt concept, though much studied by urban morphologists in the West, has been largely uninvestigated in the markedly different cultural environments of Eastern Asia. After an outline of the concept and considerations relating to its investigation in China, a fringe-belt study is carried out in the Chinese city of Pingyao. Comparisons are made with the findings of previous fringe-belt studies. The major fringe belt that has developed in Pingyao has features characteristic of fringe belts in the West but others that reflect a succession of different policies by authoritarian Chinese governments in the course of the twentieth century. The need for thorough morphological investigations as a basis for sound conservation planning is highlighted.

Recent technological and theoretical advances have helped produce a wide variety of computer models for simulating future urban land-use change. However, implementing these models is often cost prohibitive due to intensive data-collection requirements and complex technical implementation. There is a growing need for a rapid, inexpensive method to project regional urban growth for the purposes of assessing environmental impacts and implementing long-term growth-management plans. We present the Regional Urban Growth (RUG) model, an extensible mechanism for assessing the relative attractiveness of a given location for urban growth within a region. This model estimates development attraction for every location in a rasterized landscape on the basis of proximity to development attractors, such as existing dense development, roads, highways, and natural amenities. RUG can be rapidly installed, parameterized, calibrated, and run on almost any several-county region within the USA. We implement the RUG model for a twelve-county region surrounding the Jordan Lake Reservoir, an impoundment of the Haw River Watershed (North Carolina, USA). This reservoir is experiencing major water-quality problems due to increased runoff from rapid urban growth. We demonstrate the RUG model by testing three scenarios that assume (1) ‘business-as-usual’ growth levels, (2) enforcement of state-mandated riparian buffer regulations, and (3) riparian buffer regulations augmented with forecast conservation measures. Our findings suggest that the RUG model can be useful not only for environmental assessments, stakeholder engagement, and regional planning purposes, but also for studying specific state and regional policy interventions on the direction and location of future growth pressure.

This paper investigates the emergence of retail clusters on supply chains comprised of suppliers, retailers, and consumers. An agent-based model is employed to study retail location choice in a market of homogeneous goods and a market of complementary goods. On a circle comprised of discrete locales, retailers play a noncooperative game by choosing locales to maximize profits which are impacted by their distance to consumers and to suppliers. Our findings disclose that in a market of homogeneous products symmetric distributions of retail clusters arise out of competition between individual retailers; average cluster density and cluster size change dynamically as retailers enter the market. In a market of two complementary goods, multiple equilibria of retail distributions are found to be common; a single cluster of retailers has the highest probability to emerge. Overall, our results show that retail clusters emerge from the balance between retailers' proximity to their customers, their competitors, their complements, and their suppliers.

The fusion of agent-based and geospatial models represents an exciting new synthesis for social science and economics. It has the potential to improve the theory and the practice of modelling complex real-world phenomena. Yet, to date, there has been little systematic analysis at the conceptual and logical levels of how to fuse agent-based and geospatial models for the representation and reasoning of socioeconomic phenomena. Here both sets of issues are explored. In particular, it will be argued that the development of synthetic models requires autonomous agents and flexible organisational structures that can complete their objectives while situated in a dynamic and uncertain geoenvironment represented by the concept of Elementary_geoParticle. As an example of the concept, I present a preliminary conceptual model of global energy to demonstrate the validity and possible uses of the proposed technique.

Few techniques exist specifically for planning analysis. Commonly used decision techniques focus on different, partial aspects of coordinating decisions. The garbage-can model focuses on the context in which decisions emerge to explain descriptively how organizational choices are made; the strategic choice approach focuses on the relationship between decisions from which rational actions can be taken; and the decision tree focuses on the causal sequence of decisions from which the optimal path of a plan can be derived. Drawing on the theoretical foundation of these three commonly used techniques, we introduce the conceptual framework of a tool for planning analysis, namely Decision Network, that addresses context, relationship, and sequence of decisions, with a numerical example demonstrating how the decision problem can be formulated and solved. Decision Network can be used by decision makers who are faced with more than one decision in order to make plans. Much can be built on this tool to address spatial issues.

The discipline of information architecture, which borrows many of its methods and metaphors from traditional architectural practice, has so far remained largely outside architectural discourse. I examine the profession and practice of web-based ‘information architecture’ through the lens of methods and theories relating to the built environment and conclude that, although the metaphors of architecture used, for example, in the design of graphical user interfaces, have been largely unsuccessful, topological theories of architecture may offer the potential to better understand the deep structure of information as it is navigated using networked structures which are common to web-based technologies.

The decline of the downtown has been observed in many cities across the world. In response, many small cities in Japan, for example, have been making regeneration efforts including development controls on large-scale shopping centers. It is extremely useful to analyze the potential effects of relevant planning policies before implementation. We developed an urban planning support tool, a multiagent simulation (MAS) model called Shopsim-MAS, to investigate the impacts of some downtown revitalization policies through consequent spatial dynamics of shop market shares. We discuss methods to model household behavior and to understand the market area dynamics of shops. The Shopsim-MAS model developed in this project has proven to be a useful means to analyze the impact of downtown revitalization policies in Japan. It is also expected to be further expanded for impact analysis of similar or more sophisticated urban policies in other parts of the world.

There is no direct statutory planning enforcement mechanism for land without a history of Interim Development Permission Area Plans or Development Permission Area Plans in Hong Kong. Indirect enforcement of planning conditions is largely conducted by the Buildings Department upon building approval and by the Lands Department if the conditions are incorporated into the lease. The extent to which planning conditions are incorporated into leases is largely unknown, impacting the effect of this indirect contractual enforcement. The extent and probabilities of the incorporation of planning conditions in Comprehensive Development Area zones into leases are investigated. A total of 339 planning conditions on thirty-eight sites were identified but some were excluded from the study, leaving 188 for analysis. These conditions were categorised into eight types and tested with a probit model. It was found that three categories of planning conditions (access improvement, footbridges, lay-bys, and public vehicle parks; social facilities such as open space, day nursery, or kindergarten; water supply, draining, sewage) had the highest percentages of incorporation into leases, while the percentage for a fourth category (layout, landscape, car park plan) was not very high but still significantly higher than the other four categories.

During the last decade, there has been a rapid increase in the research literature dealing with the measurement of urban sprawl. Density gradients, sprawl indexes, and certain simulation techniques are some of the quantitative measures that have been used in previous studies. Fractal analysis has also been applied in describing urban areas and a fractal theory of cities has been proposed. This study attempts to measure urban sprawl using an index relating density and proximity and relating this to the fractal analysis of urban sprawl using the example of Istanbul, a large city that hitherto has not been measured or characterized using such techniques. Measures of sprawl were calculated at each neighbourhood level and then integrated within an index using ‘density’ and ‘proximity’ factors. This identifies the pattern of urban sprawl during six time slices defining five periods from 1975 to 2005. The urban form of Istanbul is then quantified through fractal analysis in the given years in the context of the dynamics of urban growth. Our findings suggest that the fractal dimension of urban form is positively correlated with the urban sprawl index when urban growth is more likely to be ‘concentrated’. This is in contrast to a negative relationship which is observed between the fractal dimension and the sprawl index when the urban growth pattern has a more dispersed, semilinear form.