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This paper is addressed to the problem of developing realistic-looking patterns of land use and activity from predictions generated by conventional urban models. The method developed is based on a geometric model of irregularity involving hierarchical cascading and recursion, whose rationale lies in the emergent field of fractal geometry. First the idea of fractals—shapes with fractional dimension—is introduced and then it is shown how two-dimensional patterns whose dimensions are consistent with a large city such as London can be simulated at different levels of detail or recursion. It is then argued that the hierarchical structure of cities should be exploited as a basis for such simulation, and it is argued that discrete choice models of individual spatial behaviour have excellent properties which enable their embedding into such simulations. The standard multinomial logit model is presented and then applied to house-type data in Greater London. A variety of models are estimated, house-type choice being related to age and distance from the centre of the city, and the spatial biases in these predictions are then mapped using prediction success statistics. These models are then used at the base level of a fractal simulation of house type and location in London. Random and deterministic model simulations are developed, and an unusual and possibly innovative feature of these simulations involves the way the inputs and outputs, data and predictions, are simultaneously displayed on the graphics device used. Conclusions for further research, particularly in spatial hierarchical modelling, are then sketched.

In this paper the detailed patterns of British property valuation and local revenue raising under the council tax are compared with those prevailing under the domestic rates. The results of matching individual council-tax valuations with rateable values for the 47000 domestic properties that make up the Inner Area of Cardiff, Wales, are reported. A geographical information system is used to identify the disaggregate pattern of properties which have been assigned higher or lower relative values after the abolition of the domestic rates. The findings are seen as significant in describing the intraurban geography of property values in Britain: properties constructed by local authorities now attract significantly lower relative valuations; pre-1919 private-sector housing is now more highly valued; and different construction types (for example, purpose-built flats, converted flats, and ends of terraces) attract quite different valuations under the two regimes. Overall, the distribution of rateable values vis-à-vis that of council-tax bands is likely to have had a multifaceted effect upon local revenue raising, and the authors begin to explore its changed geography in some detail.

The United Kingdom has experienced different local taxation regimes in each of the last three financial years: Namely the property-based household rates; the personal community charge or 'poll tax'; and the hybridised personal community charge adjusted for neighbourhood 'transitional relief'. The geographical impact of these changing policies in the Inner Areas of the City of Cardiff is examined, highlighting the importance of historical rateable values and household sizes. By using a purpose-built street-level database, the implications of the different taxation systems are examined at increasingly detailed geographic scales, and the complexity of their impact is illustrated. This analysis focuses upon the geographical effects of using administrative community boundaries for the allocation of transitional relief in Cardiff, Wales.

In this paper, we propose a model of growth and form in which the processes of growth are intimately linked to the resulting geometry of the system. The model, first developed by Witten and Sander and referred to as the diffusion-limited aggregation or DLA model, generates highly ramified tree-like clusters of particles, or populations, with evident self-similarity about a fixed point. The extent to which such clusters fill space is measured by their fractal dimension which is estimated from scaling relationships linking population and density to distances within the cluster. We suggest that this model provides a suitable baseline for the development of models of urban structure and density which manifest similar scaling properties. A typical DLA simulation is presented and a variety of measures of its structure and dynamics are developed. These same measures are then applied to the urban growth and form of Taunton, a small market town in South West England, and important similarities and differences with the DLA simulation are discussed. We suggest there is much potential in extending analogies between DLA and urban form, and we also suggest future research directions involving variants of DLA and better measures of urban density.

Yes ; Economic, physical, built, cultural, learning, social and service environments have a profound effect on lifelong health. However, policy thinking about health research is dominated by the 'biomedical model' which promotes medicalisation and an emphasis on diagnosis and treatment at the expense of prevention. Prevention research has tended to focus on 'downstream' interventions that rely on individual behaviour change, frequently increasing inequalities. Preventive strategies often focus on isolated leverage points and are scattered across different settings. This paper describes a major new prevention research programme that aims to create City Collaboratory testbeds to support the identification, implementation and evaluation of upstream interventions within a whole system city setting. Prevention of physical and mental ill-health will come from the cumulative effect of multiple system-wide interventions. Rather than scatter these interventions across many settings and evaluate single outcomes, we will test their collective impact across multiple outcomes with the goal of achieving a tipping point for better health. Our focus is on early life (ActEarly) in recognition of childhood and adolescence being such critical periods for influencing lifelong health and wellbeing. ; UK Prevention Research Partnership (MR/S037527/1), which is funded by the British Heart Foundation, Cancer Research UK, Chief Scientist Office of the Scottish Government Health and Social Care Directorates, Engineering and Physical Sciences Research Council, Economic and Social Research Council, Health and Social Care Research and Development Division (Welsh Government), Medical Research Council, National Institute for Health Research, Natural Environment Research Council, Public Health Agency (Northern Ireland), The Health Foundation and Wellcome.