Geographia Polonica (1979) vol. 42

Abstract

It is argued in this paper that it is useful to look at urban and regional systems in a relatively abstract way. The aim is to make broad but useful generalisations about urban and regional modelling. Many particular comprehensive models can then be seen as special cases which can be generated from the framework presented. The approach also enables us to note similarities between models which at first sight seem to be very different in structure.

The main objective of the paper is the development of a framework for compre-hensive urban and regional modelling which represents the minimum basis for any such model. By adding specific assumptions in various respects, many specific mo-dels can be derived.

A particular systems theoretic approach is used in the development of the fra-mework. First a systematic state description is built up in section 2. Then, a variety of methods are introduced in turn: accounting, in section 3, which enables us to keep track of system components; process-activity modelling in section 4, with particular reference to the identification of basic model mechanisms. A range of methods for model building are reviewed in section 5. Examples of their applica-tion in combination are presented in section 6 and some relationships between mo-dels explained in section 7. Section 8 contains a summary of the progress achieved by this argument in the tasks of developing a comprehensive model building kit. Various points which arise in relation to specific models are explored in a related paper (Macgill and Wilson, 1977).

A.G. Wilson, School of Geography, University of Leeds, Leeds, England
S.M. Macgill, School of Geography, University of Leeds, Leeds, England

Kazimierz Dziewoński, Instytut Geografii i Przestrzennego Zagospodarowania PAN ul. Krakowskie Przedmieście 30, 00-927 Warszawa

Emilio Casetti, Department of Geography, The Ohio State University, Columbus, Ohio, USA
Grant Thrall, Department of Geography, McMaster University, Hamilton, Ontario, Canada

Abstract

This paper is intended to provide some simple frameworks from which some pertinent policy questions can be answered concerning the slum. Accordingly, in the next section we briefly highlight the results achieved by three existing economic approaches which I refer to as ga-me-theoretic approach, competitive theoretic approach and macro-economic in-come-based approach. In the third section we establish models which clarify many of the issues raised in the second section.

Nurudeen Alao, Department of Geography, University of Lagos, Lagos, Nigeria

Dimitrios S. Dendrinos, Graduate Program in Urban Planning, The University of Kansas, Lawrence, Kansas, USA

Abstract

Here differences in urban or regional growth rates are explined as a consequence of factor price differentials. Factors move between urban aret and nation in the direction of higher returns. This lowers return differentials below alevel that would have existed in the absence of such factor movements. Analytical m)dels along this line have been formulated by Hanson and Rabenau (1976), and Ratenau (1973, 1974). The model presented here extends this work.Section 2 of this paper describes an urban area which produces a single multi-purpose output with two factors. The growth of the two factors is described b) two differential equations. It is the sum of urban internal growth and growth dte to movements between urban area and nation. The analysis of the urban growth path is simplified by the assumption that the urban area is small relative to the na ion; hence factor returns in the nation are stationary and unaffected by the factor move-ments. Section 3 describes the growth path for the case of constant returns. In Sec-tions 4 and 5 agglomeration effects are considered. For ease of exposition the cases of agglomeration economies and diseconomies are examined separately in Section 4. Section 5 analyzes the probably common and most relevant case that an urban area exhibits agglomeration economies for small and diseconomies for large sizes. It should be considered the most realistic and interesting of all cases. Conclusions follow in Section 6.

Burkhard Rabenau, Department of City and Regional Planning, The Ohio State University, Columbus, Ohio, USA

Alex Anas, Department of Civil Engineering, Northwestern University, Evanston, II., USA

Abstract

The purpose of this paper is to study the solution of Problem A under more ge-neral assumptions. In particular, though it is assumed in Fujita (1976a) that the de-mand for buildings of each type is nondecreasing with respect to time, this assumption is abandoned in this paper. As will be explained in section 7, this generalization is also necessary to obtain the solution of Problem C in Fujita (1976b) by utilizing the solution of Problem A.In this paper, we study only the optimal planning problem of urban land use within the framework of Problem A. But, note that, for each optimal planning prob-lem within the framework of Problem A, there exists a corresponding market equilib-rium problem which has the same solution (see Proposition 1 in Fujita, 1976b). Hence, the reader must keep in mind that each characteristic of the solution which we N obtain in this paper is also a characteristic of the solution for an appropriate market equilibrium problem.

Masahisa Fujita, Department of Regional Science, University of Pennsylvania, Philadelphia, USA

Abstract

The aim of the present paper is specification of theoretical conceptions, which may form construction elements of the model of dynamic organization of socio-eco-nomic space. There is a need for constructing such a model. It results from a trend towards steering of socio-economic processes in space and reshaping of spatial sys-tems of economy and society in order to give them direction corresponding with socio-economic objectives. Steering and reshaping in order to be effective and to lead towards an objective, should be based on knowledge of mechanism of processes and rules according to which spatial systems are organized. Hence, the theory of processes and dynamic organization of socio-economic space is needed.

Ryszard Domański, Academy of Economics Poznań, Department of Spatial and Environmental Economics al. Niepodległości 10, 60-967 Poznań, Poland

Oscar Fisch, Department of City and Regional Planning, The Ohio State University, Columbus, Ohio, USA

Leslie Curry, Department of Geography, University of Toronto, Toronto, Canada