The complexity of the city is increasing due to the impact of
recent devcelopments in information and communication technology
which is leading to changes in urban development processes, in
demographic composition, in cultural and political life. This
increasing complexity calls for a new integrative framework for
thinking about the development of the cities.
The use of systems view in sociology i.e. in human systems goes
back to 1950's and to in planning it is in 1970's. Systems theory
suggests that the definition, classification, are needed for understanding
and simplification. Forrester's study on Urban Dynamics indicates
that, System Dynamics is not merely a technique to provide solutions
to provide solutions to specific problems that have been formulated,
but it acts as a system methodology which determines the whole
style of problem definition, qualitative analysis and change analysis
This paper presents the case of urban planning as an example of
systems thinking and system dynamics in urban and regional planning.
It will be argued in this paper to use System Dynamics as a tool
in planning rather than accepting all the predicitons of the original
Urban Dynamics Model.
Key Words: systems view of planning, urban dynamics, systems
SYSTEMS ANALYSIS AND SYSTEMS THEORY
The system is defined as an interacting, and goal directed set
of object's taking place in an environment. The city is a system
capable of counter intuitive responses which can properly understood
and controlled only if the interaction between the basic urban
sub-systems are taken into consideration properly. In other words,
the main question is not to better understand the individual sub-system
(population, service, industry), but to understand how they act
together, how they are harmonized into this entity we call a city.
An urban region can be regarded as a complex socio-economic system.
The essential characteristics of such a system are that; firstly,
they contain a large number of variables, and secondly, many of
the variables and sub-systems are connected by feedback relationships.
The interconnections.between the sub-systems give rise to the
dynamic behaviour of urban systems. The dynamic nature of urban
systems also derives from the fact that the feedback relationships
operate over time. A basic requirement of a realistic simulation
therefore must be ability to incorporate time as a variable in
the structure of the model, in order to be able to trace the performance
or behaviour of the system through time.
Batty (1980) argues that, the tension between what is possible
in systems analysis and what is demanded by a systems approach,
has actually sustained the development of a systems theory in
Systems theory suggests that questions of definition, classification,
extent and so on are essential prerequisites to understanding;
thus, systems theory tends to widen debate about what constitutes
the system and problem of interest. In constrast systems analysis
and modelling has largely disregarded these questions.
Much more thought should be given to context, factors affecting
any problem, to ways of understanding structure and pattern.
Batty (1983) argues that in suggesting broadening of systems analytic
thinking according to the original tenets of systems theory, it
is essential to consider philosophy.
Concerning the definition and application of systems analysis;
it is argued that the major problem in relation to the problem
of definiton of "systems analysis" by planners is that
the concept refers to the substantive issues such as nature and
functioning of cities and regions. Land use modelling in the United
States in the fifties and sixties, and in Britain in sixties and
early seventies was developed in this context. Breheny (1983)
argues that the definiton of systems analysis should also cover
procedures or processes adopted in deriving plans i.e. procedural
aspects of planning.
The diagram in Figure 1, relates together the ideas of science,
which can be assumed concerning with substantive issues, and design
which can be equated with procedural, plan making activities,
with the notions of theory and practice.
|THEORY||Substantive issues, knowledge of cities, models, techniques||Theoretical processes, rational decision, model, etc.|
|PRACTICE||Applied knowledge, practical modelling||Applied processes, practical procedures.|
Figure 1.Breheny's (1983) Adaptation after Batty's (1981) Science-Design/Theory-Practice
SYSTEMS THINKING AND SYSTEMS DYNAMICS
The arguments concerning the concepts of systems thinking, system
dynamics and soft OR are presented below.
Kreutzer (1993) argues that there is no "answer" or
correct description of reality; what we perceive is interdependent
with media and language; focus on processes and dynamic structures;
nature of "living systems"; value of model building;
design the future rather than predict it. The features of systems
dynamics include: structure in social systems is comprised of
multiple, interacting feedback loops with time delays and nonlinearities;
conceptual modelling methods, simulation to test theories as keys
to building substantive knowledge about social systems. Forrester
presents the view that systems thinking does not refer to the
quantitative and dynamic analysis that constitutes real system
It is argued that (Checkland, 1989) soft systems methodology takes
"system" to be the name of an epistemological device
which can be used to investigate some of the problems in the world
and treats what to do as well as how to do it as part of the problem,
which means that soft systems methodology is a learning, not an
Lane ( 1994) argues that developments in soft OR have much in
common with current developments in systems dynamics modelling
practice, and therefore a dialoge between them would be mutually
Characteristics of the dominant OR paradigm and an alternative
OR paradigm are presented by Rosenhead (1989) below in Table 1.
Table1. Characteristics of the dominant OR paradigm and a reveral
of them to envision an alternative paradigm (Rosenhead 1989, after
| Characteristics of the dominant OR paradigm|
1. Problem formulation in terms of a single objective and optimization. Multiple objectives, if recognized, are subjected to trade-off on a common scale.
2. Overwhelming data demands with consequent problems of distortion, data availability, and data credibility.
3. Secientization and depoliticization; assumed consensus.
4. People treated as passive objects.
5. Assumes a single decision maker with abstract objective from which concrete action can be deduced for implementation through a hierarchical chain of command.
6. Attempts to abolish future uncertainty and pre-take future decision.
|Characteristics proposed for an alternative OR paradigm|
1. Nonoptimizing; seeks alternative solutions that are acceptable on separate dimensions without trade-off.
2. Reduced data demands, achieved by greater integration of hard and soft data with social judgments.
3. Simplicity and transparency, aimed at clarifying the terms of conflict.
4. Conceptualizes people as active subjects.
5. Facilitates planning from the bottom up.
6. Accepts uncertainty and aims to keep options open for later resolution.
Lane (1994) summarized the characteristics of hard and soft systems
thinking below Table 2.
Table 2. The hard and soft traditions of systems thinking (adapted
from Checkland 1985 by lane)
|Hard systems thinking of the 1950s and 1960s|
1. Oriented to goal seeking.
2. Assumes the world contains systems that can be engineered.
3. Assumes system models are models of the world (ontology-based).
4. Speaks of "problems" and "solutions."
Advantege: Allows the use of powerful techniques.
Disadvantages: May need professional practitioners. May lose touch with aspects beyond the logic of the problem situation.
Soft systems thinking of the 1980s and 1990s?
1. Oriented to learning.
2. Assumes the world is problematic but can be explored using system models.
3. Assumes system models are intellectual constructs (epistemology-based).
4. Speaks of "issues" and "accommodations."
Advantages: Available to both problem owners and professional practitioners. Keeps in touch with the human content of problem situations.
Disadvantages: Does not produce final answers. Accepts that inquiry is never-ending.
SYSTEM DYNAMICS AND CITY
Below, some of the developments on the line of Forrester's system
dynamics model is presented. The conception and development of
system dynamics took place during the late 1950's at M.I.T. under
Forrester, and although early work was in the management field,
the subject became primarily known during the late 1960's for
it's application at the macro level in urban and global modelling
by Foresster and Meadows.
Jacobsen (1984) states that a number of features of system dynamics
methodology make it suitable for testing social theory. First,
it is possible to handle many variables simultaneously, and study
their fluctuations over time. Secondly, we can take account of
multiple feedback loops in the system under investigation and
study their mutual influences, again, over time. Furthermore,
we do not have to stick to linear hypothesis, and can readily
model any nonlinear relationship posited by the theory. Jacobsen,
presents a system dynamics model to anchor it in social theory,
and states that they have found a guasi-experimental procedure
for testing macrosociological theories.
Wolstenholme (1983), reviews the development in the subject of
system dynamics. He states that the subject satisfies many of
the requirements of a general methodology, as amently sought within
the system field, as well as being a sophisticated dynamic modelling
technique. He presents a subject summary, where a clear split
is made between the system description/gualitative analysis mode
of system dynamics and the quantitative analysis mode using continuous
simulation techniques. Burdekin (1979) shows the flexibility of
urban dynamics method in dealing with the lack of the model's
spatial dimension by developing a model which simulates the development
of housing and industry over a city divided into 16 zones.
Madden (1979) criticizes Forrester's model on several points.
He states that these models do not produce counter-intuitive
results at all, and ceraful analysis of the assumptions in these
models, and the links between them, show that the results are
easily predictable. According to Madden, the faults of the model
are firstly on the assumptions of the model and the relationships
between variables that they develop, and secondly the methods
they use to link these relationships in a dynamic way. Sayer (1976)
criticizes conventional regional science and urban modelling,
mainly arquing that modellers are using the wrong paradigm.
Wilson (1978) stated that Forrester's urban dynamics model provides
a major challenge for regional science:new work will be generated
within a number of different paradigms as a result of new (and
not necessarily accepted) emphases established within a particular
paradigm. Alfeld (1995) presents his five applications of urban
dynamics. He mentions that the past twenty-five years have not
traced urban dynamics kindly.
In urban planning in 1960's architecture was dominating the profession
rather than social science. The concern was with the physical
environment, and it dealt with social processes in relation to
the physical form. The process is called environmental determinism,
i.e. the environment affected social process rather than the reverse.
Recently the concept of "total environment", integrating
natural, physical and social aspects and "strategic environmental
assessment" in under discussion and application which is
developed by the impact of systems analytýc and dynamic
The practice of using system dynamics as a methodological tool
concerning urban problems in Turkey is very much limited. Few
academic studies are existing (Erkut, 1986) is one of the PhD
thesis using urban dynamics approach. Whereas concerning systems
approach, systems concept is widely used in planning studios.
Richmond (1993)'s view on thinking skills are relevant for the
case of planning studios.
The urban dynamics model, and extensions of them, should be a
basis of future influence on political decision. First, when
modified to reflect a city's specific features, the model can
be employed as a policy guide for urban planning. Second extensions
of the models can focus on specific urban issues such as education,
transportation, and social integration. Third, the models can
provide a basis for a clearer understanding of urban processes
and a better informed perception of how different aspects of a
city affect one another.
1. Alfeld L.E., "Urban Dynamics-The First Fifty Years, System
Dynamics Review, Vol 11, No. 3 (Fall 1995)
2. Breheny BM. "Systems Analysis in Planning: A Critique
of Critiques p.107, Batty M., B.Hutchinson (Ed), Systems Analysis
in Urban Policy-Making and Planning,, Plenum Press, NY, 1983.
3. Batty M., "On Systems Theory In Urban Planning" :An
Assessment", p.423, Batty M., B.Hutchinson (Ed), Systems
Analysis in Urban Policy-Making and Planning, Plenum Press, NY.1983.
4. Burdekin R., "A Dynamic Spatial Urban Model: A Generalization
of Forrester's Urban Dynamics Model", Urban Systems
(1979), Vol 4., pp.93-120.
5. Jacobsen, C., "Sociology and System Dynamics", Dynamica,
Vol 10, Part I, Summer 1984.
6. Janet M. Gould-Kreutzer, "Foreword: System Dynamics in
Education", System Dynamics Review, Vol 9, No.2 (Summer
7. Kreutzer J.M.G., Foreword: System Dynamics in Education, System
Dynamics Review, Vol 9, No 2 (Summer 1983)
8. Lane D.C., "With a Little Help From Our Friends: How System
Dynamics and Soft OR Can Learn From Each Other, Systems Dynamics
Review, Vol 10, no. 2-3 (Summer-Fall 1994).
9. Madden, M., "Recent Developments in Urban Dynamics",
Town Planning Review, Vol 50, No 2, April 1979.
10. Richmond B., "Systems Thinking: Critical Thinking Skills
for the 1990's and Beyend", System Dynamics Review Vol.9,
No.2. (Summer 1993).
11. Sayer, R.A, "A Critique of Urban Modelling",
Progress in Planning ,Vol.6, Part 3, Eds. Diamond, J.B. Loughlin,
Pergamon Press, Oxford, 1976.
12. Wilson, A.G., Review of "A Critique of Urban Modelling"
by R.A. Sayer, Environment and Planning A, 1978, Vol 10,
13. Wolstenholme, E.F., "System Dynamics: A System Methodology or a System Modelling Technique", Dynamica, Vol 9, Part II, Winter 1983.
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