Conference Proceedings

The 12th International Conference of the System Dynamics Society

1994 Stirling, Scotland

 

The following papers were presented at the conference in parallel and plenary sessions. The original printed proceedings, edited by Clare Monaghan and Eric Wolstenholme, were printed in hardcopy and distributed at the conference. Below please find the Paper Index for these proceedings, including an abstract. Papers are listed alphabetically by the last name of the first author. To find a paper by an author who is not the first author, simply search on the author's name. Available papers are Acrobat (.pdf) files and can be read using Acrobat Reader available from http://www.adobe.com.

For details about purchasing a copy of the printed proceedings, visit our website System Dynamics Society or send an email message to system.dynamics@albany.edu .

PAPER INDEX - listed alphabetically by first author:

Using Cognitive Mapping to Develop a Large System Dynamics Model

Fran Ackermann, Terry M. Williams, Colin Eden, Andrew J. Tate

 

This paper describes the use of System Dynamics (SD) for making a claim for Disruption and Delay.  The case concerns design management of a large development project.  Extensive group workshops (GDSS) with the managers, based on the cognitive mapping technique and association software tope COPE, showed that the client-contractor interaction process had set up dynamic feedback loops creating Disruption and Delay to the project.  In order to qualify the extent of the Disruption and Delay, the cognitive map was transformed into an "influence diagram" and thence through the acquisition of numeric data into a large SD model.  The development of the two continued in parallel, informing and checking one another.  As well as simply providing explanations of trends and behavior, the SD model had to reproduce the planned and actual out-turns explicitly for it to be a creditable explanatory tool.  The paper will draw lessons from the case study on the process of moving from cognitive map to a SD model, and the mutual benefits of joint development, as well as more general lessons about combining soft and hard methods.

 

Design Guidelines for Participative Business Modelling

Henk Akkermans, Jacqueline Bosker

 

This paper describes the evaluations results from an unsuccessful case study.  In this case study, system dynamics modeling was used to support the development of an implementation plan for a corporate strategy.  Three modeling sessions were conducted with senior management, which were unsuccessful.  A detailed analysis of the evaluations interviews with several of the participants had identified the main cause for this failure.  These causes turn out to be threefold:  Firstly, most of the participants were unwilling to discuss openly this politically sensitive issue, secondly several errors were made in project design and thirdly the scope of the strategic issue is at stake was too broad to tackle effectively within the time frame allotted to the project.

Several important lessons are drawn from this project.  These lessons are formulated as designs guidelines for future system dynamics modeling as such, but rather to underlying management consulting skills required to conduct any strategy support project with senior managers.

 

Feedback and Control in a Product Portfolio Management Model

Arthur W. Allaway, Giles D'Sousa

 

An optimal control-based decisions support model is developed which allows managers and future managers to gain hand-on experience with product portfolio management in a dynamic micro-world.  In this micro-world, they study one of the several scenarios, set objects and importance hierarchies, create action plans and control the system over time en route to their objectives.  The system is demonstrated with data from an actual product portfolio management case.

Using the system, a manager or player can gain sophistication with decision-making as well as assess the capabilities of dynamic models for decisions support.  Working with the models gives players a feel for such important insights, as the lag effects of response, the differential impact of various marketing tools, cross-elasticities, and the potential for cannibalization. A manager can devise promotional strategies to achieve specific sales results for a particular brand or product line, test those strategies, and learn as the system evolves.  Backing up the micro-environment is a discrete-time optimal control model which allows the system to be optimized from the perspective of a decision-maker.  Players can test their own strategies against those of the optimal control "Shadow Player".

Used as an optimization-based simulations tool, the model allows flexibility in the testing of alternative strategies and scenarios which affect achievement of product portfolio objects.  The model focuses on the overall objectives of the portfolio while recognizing the objectives and dynamics of the products within it.

 

Managerial Conflicts in Social System: The Ignored Significance of Ethics and Values

Irma Alm

 

A social system is unlike a natural system, because its behavior is determined by ethics, values and purposes.  Yet it can be compared to a natural system in terms of self-maintenance.  To maintain itself, a social system reproduces roles, functions and authorities, not it's basic components, individuals.  This is because, social system are purposely designed by human begins for human purposes. The ethics which guides management of social system is a kind of rule ethics relying on rules of behavior, laws, and taboos.  The rule ethics and its basic value, rational calculation, disables the possibility of social system to cope with rapid or serve environmental changes. It also creates managerial conflicts which are difficult to solve within the frame of reference of the rule ethics and its association values. These conflicts are results of the tension between: control and semiotic freedom, shared culture and diversity, and command hierarchy and self-organization. To diminish these tensions, we need another kind of ethics, an increased development of human consciousness.

 

Scripts for Groups Model Building

David F. Anderson, George P. Richardson

 

For the past seven years, the modeling group at the University at Albany has been experimenting with techniques for building system dynamics models directly with groups.  This paper extends the previously reported work by discussing specifics scripted techniques used to implement the group modeling building approach. 

Our purpose is to initiate a larger discussion of shared scripts and techniques for group model building.  The discussions is divided into planning for a group model building conference, scheduling the day, particular scripts and techniques for various group model building tasks, and closing a group modeling conference. 

 

Mental Models and Dynamic Decision Making in a Simulation of Welfare Reform

David F. Anderson, Terrence A. Maxwell, George P. Richardson, Thomas R. Stewart

 

This paper is the second in a pair presented in this volume. The first paper presents a theoretical view of mental models appropriate for carrying out empirically-based research on system dynamics modeling interventions. Mental models consist of three types of measurable sub-models – end models, means models, and means-ends models. The means-ends models may be thought as containing either detailed “design” logic or much more simple “operator” logic. This paper presents an empirical test of the impact of interventions intended to improve design versus operator logic for 53 participants in a dynamic learning laboratory with a task centering on implementing welfare reform over a simulated twenty year period. Results suggest that providing managers with high level heuristic results from modeling interventions is necessary condition for achieving improvement in system performance. Focusing on operator logic is key to improving managerial performance of dynamic tasks.

 

System Dynamics applied to Analysis Modeling and Simulation of Chain Growth Polymerization Process

Hugo Andrade S., Alvaro Ramirez G, Ana C. Uloa Q, Sofia Uloa Q

 

The problem to be addressed is the dynamics of the chain growth polymerizations process via free radicals.  The process consists in a series of chemical reactions by which a macromolecule is formed by the addition of many structural unites called mers.  The reactions taking place are initiation, propagation and terminations of the growing macromolecule or molecular chain. 

The problem was focused under the General Theory of Systems and the methodology of System Dynamics.  This work is an example of interdisciplinary interaction between Chemical Engineering and Systems Engineering through System Dynamics methodology.

The modeling of polimerization processes is an up to date topic of both scientific and industrial practice importance.  The developed model is based on the especies balance equations and also on an isomorphism with population models. 

The model is composed of a set of only sixteen, but very complex non-liner differential equations, whose solution is very restrictive with respect to the simulation time interval used, due to the great differences in order of magnitude of the characteristics time of occurrence of the various events taking place in the process. In this particular, the authors consider to have made a contribution to establish criteria to quantity what is called in the literature as the appropriate simulation time interval.

The proposed model is ahead of the traditional models of polimerization, in as much as the second ones predict only the behavior of the stable species and the chain lengths average, whereas the proposed model includes besides the dynamics of the unstable species. On the other hand, the proposed model excludes the seudo-stationary assumption, on which, according to our results, is not a completely valid.  As a general conclusion, the Dynamics System methodology appears to be an effective problem-solving tool in interdisciplinary environments.

 

ECOMAN - An Environmental Management Simulation Game

Paula Antunes, Rui Santos, Luis Jordao, Helder Alves, Joao Pedro Rodrigigues

 

Environmental management is a complex dynamic process, which involves taking decisions regarding different environmental components and socio-economic agents. Within in the contexts, simulations games are extremely powerful learning tool, allowing the decision maker (player) to formulate and test the results obtained with the implementation of alternative environmental managements strategies, which is often impossible to perform in real situations.

ECOMAN is a simulation game, where the players are environmental managers who are responsible for a region, trying to cope with the different agents, media and uses in order to achieve environmental quality, and social welfare objectives.  
The player has a limited budget to allocate to several environmental management tasks, which is dependent on the health of the economy of the region. Each year a score is computed taking into account environmental quality, service levels and economic activity.
The game is based on a system dynamics model developed in STELLA II, simulating the major interactions between the socio-economic and the environmental system.  The model was implemented with a multimedia interface integrating numerical, graphical and qualitative information using Supercard and Quicktime for the display of video images.

 

A Dynamic Model of Quality Cost and Benefits Systems for Design Quality

A K Bajpai, P C T Willey

 

The Importance of quality cost benefits is sometimes not fully recognised by industrial managers.  Quality cost money.  Industrial managers recognize this and tend to be afraid of spending on quality.  But quality also earns money.  Industrial managers do not seem to be fully convinced of this fact.  Unfortunately, even existing literature on the subject does not encourage investing for higher quality.  Most of the cost models about quality deal with the quality improvement and the costs associated in achieving the desired level of quality, but fail to incorporate the benefits of improved quality.
In this work, an attempt has been made to develop a quality costs model which incorporates the benefits.  The quality cost elements have been drawn from various standards sources such as British Standards and American Society for Quality Control publications on quality cost.  The benefits from investing for quality are taken from recently published case studies and reports as well as from our own experiences.  The elements of quality related activities of design department, such as design standards, training design staff and test equipment are identified. The contribution of each individual element, starting from estimation of looses due to poor design to preventions of poor design is isolated and linked dynamically so that costs and benefits are demonstrated through time. 
The quality costs and benefits model was developed using the System Dynamics Modelling approach and simulated using the computer software package “Professional DYNAMO Plus”. The simulated results demonstrate the extent to which prevention investment is justified by future earning.

It is felt that the model can be a significant addition to course material for training programmes of industrial managers.  It allows the user to explore the consequences of different quality management policies such as the amount of investment and the nature of investment on the profit performance and delay before profits are increased in and organization. It is hoped that the model will serve as a useful tool in the hand of decisions-makers, encouraging them to invest more in prevention activates.

 

Defining System Dynamics Education

Yaman Barlas

 

This is the second paper in a series that aims to start a debate on issues involved in university-level system dynamics education.  The first paper argues that the field has not experienced growth that one would expect from its potential and identifies several issues that need to be addressed by the system dynamic community, before the field can proliferate in universities.  The second paper tackles some of those problems.  More specifically, the paper discusses the academic definition of system dynamics:  What is the academic core of system dynamics?  What other objects are immediate relevance and importance with respect to this core. The paper offers answers to those questions.  The second issue that the paper deals with is the problem of terminology.  I discuss different types of terminology problems, the most significant being system dynamic, the very name of the field.  System dynamics having an established meaning in mathematical and engineering sciences, does not convey the specific meaning that we wish to attach it. I discuss various potential problems caused by this situation.  I then offer a short list of alternative, more specific names for the field. I conclude that, once the academic issues are rigorously tackled, the university-level system dynamics education should experience growth, which would be a major step toward activation an exponential growth process in the field in general.

 

Model Validation in System Dynamics

Yaman Barlas

 

Model validation constitutes an important step in system dynamics methodology. Validation is a prolonged and complicated process, involving both formal/quantitative tools and informal/qualitative ones.  This paper first provides a summary of the philosophical issues involved in model validation.  We then focus on the formal model validation. We offer a flowchart that describes the logical sequence in which various validations activities must be carried out.  We give examples of specific validity tests used in the three major categories of model validations:
Structural tests, structure-oriented behavior tests and behavior pattern tests.  Finally, we focus specifically on the logic of the behavior pattern validation and illustrate it on a mutli-step validation procedure. Currently, we are in the process of implementing this multi-step procedure on micro-computers, embedded in a friendly user-interface.

 

Introducing MIS: A Process of Directed Organization Change

Ronen Bar-Nahor, Chanoch Jacobsen

 

Despite the importance of computerized information system, many MISs are left idle or used only partially, having exceeded their budgets or time allocations.  The basic problem is that critical interactions between software engineers, users, and the organization have been neglected.  The reason for this neglect is the inter-disciplinary nature of the problem.  There is a basic conflict of interest between managers’ need for efficiency, users’ desire for quality of working life, and software engineers' quest for sophisticated technical solutions.
We have developed an integrated theory of the detailed processes and transformed it into System Dynamics model.  Running the model against three time series of data from one organization that has introduced an MIS, we reproduced an average of 84% of the variances in the data.  Our tentative conclusion is that introducing MIS is a special case of directed organizational change that requires cooperation between software engineers and OB experts.

 

Scenario Modeling of Demand for Future Telecommunications Services

Jeremy Barnes, Fraser Burton, Ian Hawker, Michael H Lyons

 

It is widely believed that the world is entering the Information Age, and telecommunication companies must make critical investments decisions based on how much information customers will want to move in the future, Understanding and preparing for the range of possible customers demand scenarios is vital for long-term success in an increasingly competitive market.  However, detailed forecasts are impossible to make since the market is as yet undefined.  Scenario modelling is useful in developing the understanding telcos need to achieve success.
We have developed a system dynamics model to investigate the effects of different business and technological drivers on the demand for future telecommunications services, using the software tool iThink.  Drivers include the number of people teleworking and increasing computing powers.  These interact to produce usage dynamics for generic services covering conversation, messaging and data transfer, which are then used to calculate resulting network traffic. 
Our results suggest that the key uncertainties are the rate of improvement in general IT sophistications, and the extent of teleworking.  High growth in both of these produces rapid growth in peak traffic, whilst low teleworking delays that growth.  Slower improvement in IT sophistication severely limits growth, since increasing computing power could stimulate large volumes of traffic.  Small increases in the use of video applications also produce significant traffic growth, and these factors combine to give large uncertainties.  The behavior of this system is discussed with reference to individual business sectors, demonstrating system dynamics as a useful approach for investigating telecoms supply-demand systems.

 

Illusion and Reality: A Systemic Approach to Management Development Workshops

M A Barrett, B Crellin

 

We describe the development of a meta-level framework to be used as a structuring and controlling mechanism during management development workshops.
The framework is constructed around the use of system metaphors and methodologies within a microworld workshop environment.
Relevant elements from system methodologies are employed as transitional objects within these microworld environments, in order to provide a creative stimulus and reduce participant anxiety.

 

The Management of Urban Water Services - A study in Long - Term Institutional Dynamics

John Barton

 

The paper uses systems thinking to interpret the dynamic interplay between social, political, and institutional forces that have influenced the management of a large urban water authority.  This interpretation is used as a framework for assessing recent government initiatives to introduce competition into the water industry. The study is based on 100 years of history of the operation of Melbourne Water and current proposal to vertically disaggregate the business and to use a combination of industry regulation and yardstick competition to manage the industry.  The paper attempts to demonstrate the importance of adopting a systemic approach to understanding the complex array of issues involved and to record some of the practical difficulties encountered in using this approach within a highly turbulent environment.

 

The Introduction of Hospital Information System - The Necessity for Accommodation

P J Baugh, D M Walters

 

This paper examines the introduction of information system into the new environment of the National Health Service since restructuring in 1989.  Taking its approach from Soft Systems Methodology, it looks at cultural analysis in the context of the development of decision support systems for hospital managers and medical staff.  Drawing on the deeper cultural analysis developed by Schein, it examined the problems which face systems developers when attempting to seek an accommodation of views between groups which not only have different requirements but significantly different outlooks predicated by their roles in the hospital environment.  Particular attention is focused on the survival instincts of these two groups when faced with an environment which is changing rapidly.  The medical profession is seen as one which sees its former pre-eminence within the hospital threatened.  This may have adverse effects on the development of system for doctors and managers alike but, unless the cultural dimension is addressed, solutions to hospital information problems will, at best, be partial.

 

Investigation Software project Resource Planning: An outline of a Proposed Multiple Case Study Research Approach

G A Bell, J O Jenkins

 

The use of system dynamics (SD) is proposed to assist project managers in examining the consequences of their resources distribution plans.  Justification of the selection of this technique is given, in particular why it is purposed as an alternative to statistical forecasting techniques.  The focus of the research is to provide insights into how to reduce schedule slippages, which is thought to be a common dynamic behavioral problem.  One objective in reaching this goal is to identify common SD structures.
An overview of the original SD research contribution to the software engineering discipline is given.  A brief description of the problem tackled and the model findings are outlined.  Criticisms of the research process are developed to justify parts of our approach.  To ensure that this practical research investigations is both relevant to managers and scientifically rigorous, a selection of both qualitative and quantitative methods are suggested to assist with the first objective.  These are briefly justified and discussed in this paper.

 

Systems Thinking and its Influence on Operational Culture

J B Bentham, A G de Visscher

 

This paper reviews a recent period of change in traditional manufacturing environment of a large oil refinery, and the role of systems thinking techniques in this development process.  The focus in on how the gradual adoption of these methods as part of normal working practices has contributed to changes in attitudes, behavior and performance.  Attention is directed to the way the methods are themselves proving to be a vehicle for cultural development, as well as being of the toolkit used to analyse specific issues.

The paper describes the way several techniques have been introduced, applied and combined.  There is a commentary on how these approaches have helped to induce a shift from a rather intimidating fire-fighting mentality to a widespread embrace of the quest for structural improvements.  This shift and the adoptions of the techniques are, of course, mutually reinforcing.  What is of particular significance is the way the virtuous circle was initiated.  It is concluded that the approach was successful largely because it was consistent with the broader requirement of change-management and compatible with fundamental aspects of the predominant organizational culture.
While this is an ongoing process of transformation, the paper introduces a framework to conceptualize the insights which have emerged so far.  It is intended that this will facilitate their further application and hence support the broader learning process.

 

Dynamics of New York City Court System

Dan S Bernstien

 

For policy makers in New York City the functioning of the criminal justice system appears to be deteriorating.  During the last few years arrests by police have dropped.  However inmate population continued to increase for over a year after the drop in arrests.  In spite of the drop in court case, or case load per judge, the average length of time to dispose of a case continued to increase.  During this time, the total number of judges working in New York City increased, further dropping the average caseload.
The importance of this topic lies in the resistance of the criminal justice system to change and the high total cost of the system.  Recent policy goals of New York City management have been to reduce needed jail capacity by reducing both the intake of inmates and average lengths of stay.  New York City officials estimated that by reducing the inmate length of stay by ten days savings of $108 million could be realized.

 

A Pocket Model of Global Warming for Policy and Scientific Debate

Dan S. Bernstien, George P. Richardson, Thomas R Stewarts

 

The global climate is a large complicated system with many feedback loops connecting the different sub-systems.  In recent years there has been an increase in the public's awareness of global warming and the greenhouse effect.  The public understands that there is some connection between the human emission of greenhouse gases and global climate change.  Experts in this field have been analyzing these connections for years and are still unable to give definitive answers to questions concerning the direct link between emissions and temperature change.  Policy makers have a desire to intervene in order to limit the amount of emissions.  At this point in time available answers are under debate and are unclear, or the model used by the scientific community are too complicated for policy makers to understand.
The purpose of this global warming model is to be small, conceptually clear, and accessible to nonscientists.  The model contains all of the feedback loops hypothesized in the scientific literature.  However, due to its small size it is aggregated to a global level.  This level of aggregation will help to make the model more understandable for policy makers.  The global aggregation will allow policy makers to focus upon the global effects rather than the details of the climate system.

 

A System Dynamics Model of Soybean Production in India

B S Bisht, K C Sahu, K Vizayakumar

 

An effort has been made to develop a system dynamics simulation model for soybean production in India.  Soybean has been a relatively new introduction to Indian agriculture as a cash crop.  Soybean industry in India is typified by high (1520\%) annual growth in area as well as production.  It is also capacity as compared to the annual productions. Soymeal has been a major earner of foreign exchange for the country with advancing years.  The model presented here analyses the mechanics of flow of area between various crops options, productivity of soybean and competing corps, annual production, prices and the benefitcost ratio.  The values of constants were determined through survey of farmers and expert opinion poll.  Policy options have been analysed with the objective of higher profitability for the growers in the long run.

 

Dynamics of Management Development and Enterprise In Eastern Europe

Andres Breiter, Edoardo Mollona

 

Privatization of most enterprises in Eastern Europe is considered essential for the democratic form of government to survive over an extended period.  The dynamics of the privatizations processes and of management development are very important but they have received very little attention.  They are crucial to the success of the attempted conversion of the system in that part of the world.  This is stunning because of the several billion ECU's and U$S spent on economic and management advice to the countries in the area.
This paper explores the dynamics of management development to meet the needs as markets are freed and companies are privatized.  Particular attention is directed at the fact that many needed skills essential to success may not be taught in the normal management school programs.  From this observation emerges the need for a program of management development uniquely designed for recently privatized companies and for those soon to go through the process.  In addition the conclusions contribute insights to the current debate whether to privatize all corporations within a very short period or whether to proceed more gradually.

 

Strategic Cultural Interventions in Systems Science - Examining the Prospects for the Further Development of Methodological Complementarism

John Brocklesby

 

This paper contemplates the prospect of the complementary use of hard, soft, and critical systems methodologies, becoming a more established practice among the diverse company of operational researchers and management scientists in academic, commerce and government, who have been trained in systems thinking and apply its language and concepts in dealing with organizational problems.

The paper takes the line that because matters concerning methodology always embody deeper structures of meaning, and meanings are largely culturally determined, it is worthwhile drawing upon ideas from the literature on organizational culture to illustrate some of the key factors that are likely to obstruct this and other similar initiatives.  From a culture prospective, transitioning from the existing specializations of systems science towards methodological complementarism is conceptualised as requiring a form of organizational learning.  Learning is contingent upon the existence of a broad set of propitious circumstances; a scenario, it is argued, that is not met in this particular case.  Although the idea of complementarism is the principal focus of the paper, much of the argument applies equally to other attempts to deliberately intervene in the culture of systems science.

 

Efficient Parts Supply: Influence of Information Flows

S J Byrne, L Roberts

 

We investigate parts supply from one supplier to a manufacturer who operates a very variable final assembly schedule with kanbans for parts supply to the production line from suppliers.
The information flow includes kanbans for resupplying the line from the factory store and restocking the factory store from the supplier, one week ahead forecasts of parts requirements, 8-week ahead requirements and updates orders supplied weekly, and a six month MRP schedule supplied fortnightly.  The supplier uses these to schedule raw material preparation, initial assembly on a bottleneck machine, and finishing.  This is challenging given the conflicts between the pieces of information.
We investigate ways to improve total system performance, particularly inventory levels and easier production scheduling of critical machines, given the delays and structure of the system, using system dynamics models built in ithink!
Kanban numbers can be reduced without risking production interruptions.  The one week ahead forecasts offer little useful information to the supplier.  Shifting to a simpler scheduling mechanism for the initial assembly is helpful.
We have investigated two processes in the manufacturing logistics system, parts flow internal to the manufacturer and to the supplier, and the linkage between parts usage by the manufacturer and parts production by supplier.  They can be simplified and improved, reducing inventory holding and hence cost, without compromising the overall responsiveness of the manufacturer which is a distinctive competitive characteristic.  Simplified information flow processes allow for easier, better operation of total system.

 

The Paradox of Rational Policies and Irrational Outcomes: A Case of Unexpected Policy Performance Caused by Information Delay

IK Jae Chung, Dong Hwan Kim

 

The study analyzes the impact information network within the waste recycling market on the performance of public policies designed to develop the recycling market.  Two typical policies are reviewed with an experimental procedure of partial and whole model tests.  A system Dynamics model of waste recycling market is used as a laboratory setting for this study.  The research findings suggests that well-intentioned policies can inadvertently lead to dysfunctional performance within a localized information environment.  Delayed and distorted information feedback in the multi-stage structure of the recycling market further complicates problematic policy outcome, or market instability.  This study proposes an information policy of integrating vertically the information network in the recycling market in order to improve the performance of market development policies

 

A Policy Making Framework for the New Zealand Wine Industry

J F S Cooper, J O Chester, R Y Cavana

 

This paper discusses the dynamic simulation model of the New Zealand wine industry which is being developed at Victoria University to examine the impact of environmental and policy changes on the short and long term behavior of the industry.  It is highly aggregated model which includes sectors for: planting and harvesting of grapes; production, exports and imports of wine; stock movements and financial flows.  The model provides a policy making framework for the analysis of changes in grape yields, climatic conditions, excise duty on domestic consumptions, minimum grower returns, exchange rate movement and international competitiveness.

 

Integrating Archetypes and Generic Models into a Framework for Model Conceptualisation

David A Corben

 

Model conceptualisation is the most difficult system dynamics skill to acquire, practice and teach.  The advent of user friendly simulation tools; STELLA and ithink, have made the task of model constructions and use much easier.  Model conceptualizations by contrast remains as difficult server as ever.
Experiences in training managers in system dynamics show that it is a relatively simple task to turn complete beginners into competent and confident simulators.  The capability to recreate a model from ithink map and in a written description of operating policies is quickly acquired, as is the ability of modifying that model set to test out possible solution to problematic behavior.
The problem arises when these proficient simulators are asked to conceptualize a simple two loop model from a problem descriptions, presented in the form of a newspaper article.  This task is found very difficult by most course members.
The paper describes the development of a new technique to assist with the model conceptualisation process.  The method integrates archetypes and their corresponding generic Models into a framework that helps modellers move from a problem descriptions to a first past ithink model and/or casual map.
An application of the method, to aid conceptualisation of a model of Government funding of housing association is described.

 

Learning Maintenance Management through System Dynamics

A Continuous Improvement Process

Adolfo Crespo Marques, Ruiz Usano

 

Maintenance management has become a field of important development according to the operating needs of production planning systems and the impact of new technologies in the industry.  The processes of production flow creation and inventory control in the modern factories lead to a more sophisticated maintenance system to ensure low failure rates and reduce accordingly failures consequences, which is a must in these kinds of environments to meet the production schedules.
In this paper a maintenance system is modelled to study the effects of different policies that can be applied to reach above mentioned targets.  Moreover the conditions required to create a continuous improvement mechanism for the system are analyzed.  Model validation and simulation results are obtained and presented for a real problem in the Spanish industry.

 

Projecting Model Behavior in the Absence of a Model: Results of a survey

Brain Dangerfield, Carole Roberts

 

One of the advantages commonly put forward in support of the system dynamics methods is that managers find it difficult to trace dynamic consequences of cause and effect relationships even in simple systems.  While this may be intuitively appealing as one of the justifications for existence of system dynamics, there is a need to accumulate a body of evidence which results from putting this assertion to the test. The paper reports the findings from a questionnaire which has been administered to over one hundred undergraduates and postgraduates covering a range of business management specialisms.   Respondent were asked to decide between two manufacturing technologies, exhibiting quite dissimilar cost structures, with a view as to their future profitability under four different demand scenarios.  The questionnaires were administered twice with a three month gap between during which the answers to the first one were revealed, and on the second occasion the rubric was altered to incorporate feedback into the situation described.  The competing technologies and their associated cost structures reflect very real policy choices and so the outcome of the exercise has a message for manufacturing industry as well as the system dynamics community.

 

Perspectives on Teaching System Dynamics
Coupling structure and behavior, annotating simulations, and supporting Just In Time Open Learning (JITOL)

Pal Davidsen

 

In system dynamics we seek to understand the relationship between the structure and the behavior of dynamic systems.  In problem solving, for instance, we must identify the structure underlying problem behavior and find how the structure can be modified to create a more desirable systems behaviour.  To enhance such an understanding, we utilize the graphical techniques.  Whether in print or in software, however, there has been a significant gap between our representation of structure and behaviour.
In this paper, we first present a series of ways to link structure and behaviour such that behaviour can be more easily understood on the basis of the underlying structure.  These techniques are computerized using PowerSimTM.
Within the framework of an EEC research project on distance education for professionals, JITOL (Just In Time Open Learning), we have investigated how to facilitate System Dynamics distance education on electronic networks.  One of the main challenges consists of finding an effective way to present the results of a simulation. Such an interpretation of simulation results is normally partitioned in accordance with the various phases of the system development, portrayed by the simulation, and requires that references be made to the assumptions embodied in the underlying simulation model.
Consequently, the author or any other user of a model must be allowed to comment on the various phases of a specific dynamics development.  Moreover, these comments must be made available to any reader of the model, ie anyone who runs the model under the conditions specified by the author or user.  And these readers must be allowed to respond by adding their own comments to the same fragments of the model development.
This paper outlines a technique developed to, at runtime (ie as the model is running), link such annotations to graphs that represent simulation results, and to make such annotations available to readers at runtime when they inspect that specific simulations.

 

Der Rutli Management Simulator - a new concept in system dynamics based management fight simulators

Pal Davidsen, Magne Myrtveit

 

A new management institute, Der Rutli Fuhrungskrafteseminar, was established in Germany this year.  Its leadership is committed to the teaching of management based on the principles of System Dynamics.  As an element in the promotion of these ideas, a new System Dynamics management simulator has been developed.  There are several ways in which this simulator constitutes a new concept in management training.  In particular, we have addressed the issue of teaching policy design, supplemented by design making.
The properties of the simulator originate from the characteristics of the underlying software.  Consequently they can be applied generally to any system dynamics based management simulator.  In particular, the simulator;
(1) the simulator is a multi-group simulator utilizing any personal computer network that supports MS windows;
(2) The simulator allows the user not only to submit decisions to the server that calculates and returns a new state, but also to formulate and try out, on their local computer, their own strategies over any strategic horizon;
(3) the simulator gives the user access to;
-the underlying simulation model (to an extent determined by the administrator);
-The tool by which the simulation model was built, allowing the users to formulate and test their own dynamic hypotheses.
In this paper, we describe these characteristics of a new generation of simulators for management training, illustrated by Der Rutli Management Simulator, and we discuss the potential implications of taking advantage of these characteristic.

 

Possibilities and Challenges for System Dynamics Research and Education in Europe

Pal Davidsen

 

In October 1993, a group of 7 academic institutions submitted to the ERASMUS Office of the European Union (EU) in Brussels an application to establish an Inter-University Corporation Program (ICP), i.e. a student exchange program, in system dynamics. This initiative is coordinated by the Department of Information Science, University of Bergen, Norway. A first response is expected by the end May 1994 and the final decision will be known in July. The program will be implemented during the academic year 1994-95.

When the ICP is established, it will receive a grant to support a number of students visiting host institutions abroad in order to receive a formal training in the theory and practice of system dynamics. The program will also support the exchange of faculty and system dynamics curriculum development.

The system dynamics method has proven particularly useful in social sciences and in public and private management. A large number of enterprises currently apply system dynamics in their design of policies and in management training. The system dynamics method is taught and applied in prominent management schools, schools of social science and technological institutes in Europe, America, Asia and Australia. Although originating and partly dominated by American Universities (MIT in particular), there is a large numbers of courses in theory, applications, and software development taught in Europe. It is our purpose with this programme, by joining forces, to emphasize this European tradition of the field.

This paper describes some possibilities and challenges that arise from this program. It also indicates how we could initiate a research program in Europe, possibly an ESPRIT-program, based upon system dynamics.

 

The Applications of System Dynamics to Re-Engineering Career Plans

Andrew Davis

 

This paper demonstrates the use of system dynamics in the examination, evaluation and reformulation of business policy.  It describes the consultancy and modeling process used to examine the recruitment and promotion system of a large company.
The management felt that the short-term decisions they were making, particularly about how many graduates to recruit, were endangering their ability to manage the system in the longer term.  They were finding the there were too many staff at middle management grades, whilst they were doubtful that they were developing the senior management of the future.   They further believed that the system, as currently operated, gave them little ability to control the long-term availability of staff.  It was decided to initiate a study, using system dynamics, to understand the dynamics of the manpower system and study the policy options available for controlling the system.  The model enabled management to increase their understanding of the system and evaluate their current method of decision making.
The model demonstrated that the problems were indeed caused by the system, and that managers had adapted their decision making process close to the optimal, given the constraints in which they were operating.  A new system of recruitment and promotions was defined, tested and implemented, which overcomes many of the problems identified in this study,

 

Helping Not-for-Profit Enterprises Become More “Business-Like”: A Learning Organization Approach

Eric Deakins, Graham Winch

 

This paper describes the results to date of an investigation into the role of a system dynamics “microworld” model in helping a not-for-profit organization (charity) become more “business-like” in its strategic management, and more able to evaluate impacts and opportunities in its ever more competitive environment.  The organization- the local division of a relationship advisory service in the U.K. - in common with most other charities is facing a more turbulent environment with major uncertainties in government grants, greater competition for voluntary donations, and changes in its perceived role.  This requires the organization to put much greater emphasis on effective management, but this may be regarded as diverting, and even in conflict with deeply held beliefs, by Board members, paid managers, and counselors and volunteers.
This experience to date suggests that the development and utilization of a microworld model of the organization and its environment help its member to envision the full implications of possible strategic developments.  These developments include the impact and timing of direct advertising and the offering of contract advisory services to firms concerned that redundancies and other situations may put their employees under the sort of stress that could seriously effect their domestic relationships.  This approach clarifies and aids the reconciliation of "business" performance measures like client contributions, cash flow management and training investment with such core concerns as counselor moral and the service provided to it's "clients".

 

Information, System, Hence, Information System: The case for Ontological and Epistemological "depth"

Thierry Demay, Christian de Cock

 

This paper presents a critique of the atomistic ontology and empiricist epistemology which inform most current definitions of the concepts information, systems and, hence, information systems in the Information System (IS) literature.  The notion of information as an objectively given quantifiable 'force' emanating from the real world and endowed with the essential property of dissolving uncertainty; or as possessing the same essential property but as consisting of structured or processed data, i.e. atomistic ‘facts’, about the real world are argued to be unsustainable, on both philosophical and practical grounds.  It is argued, furthermore, that the notion of systems as an ontology in respect of goal seeking cybernetic machines unproblematically specifiable in terms of their boundaries, of their input and output, and of their objectives is not inappropriate to the socially-based systems in terms of which an IS must be defined, but also fails to consider the ontological, and consequently epistemological, depth implied by this concept.  In view of these arguments, an alternative conceptual practice is explored by suggesting that the concept system be taken as an epistemological tool to be deployed in respect of complex coherent 'whole-entities' characterized by their emergent properties and, in the case of socially-based systems, by the essential autopoietic nature of their modes of regulation and self-representation including, above all, language.  It is also suggested that information should be considered as a set of fundamentally, arbitrary signs whose 'emergent' properties i.e. syntactic, semantic and pragmatic, are intersubjectively negotiated between international organizational agents and, as such, inseparable from the forms of social life which they sustain and in which they are generated.  This alternative conceptualization, proceeds from an ontology which acknowledges the essential 'depth' of its key thought objects, by virtue of the emergent properties attributions to these objects, in contrast to the flat atomistic ontology currently dominant in the IS field.  Such an alternative conceptual practice, we argue, provides an initial theoretical framework in which to ground the currently ill-defined, “emergent perspective”, on the relationship between ICT and organizational change, identifiable in the IS literature.  While as regarded IS practice, this re-conceptualization is found to be congruent with the object oriented approach to IS development which is currently attracting increasing practical attention and which appears to provide the basis for a common and intuitively meaningful language with which to bridge the gap between IS end-users and developers.

 

Responsibility Analysis: A Basis for Understanding Complex Managerial Situations

Gurpreet Dhillon, James Backhouse

 

Management practitioners have always felt the need to understand organizational contexts and processes.  Consequently many different theoretical bases have been used to facilitate the evaluation.  However the focus on existing approaches has primarily been on the ‘formal’ aspects of the organization.  This has often resulted in inadequate and poor analysis of various complex managerial situations.  In viewing organizations as communications systems, this paper introduces the responsibility analysis approach which helps in presenting a comprehensive picture of an organization environment.  At a very generic level, organizations are viewed in terms of three sub-systems; technical, formal and informal.  When conducting a responsibility analysis, the endeavor is to identify the responsible agents and capture the norms associated with each action.  In doing so, we seek to understand the underlying repertories of behavior.  This produces a high level specification of the organization and its attendant responsibilities, thus allowing a comparison to be made with the implicit and explicit structures of responsibility.  The paper demonstrates these concepts with examples drawn from a National Health Service case study.

 

Feedback and Breakdowns as Breakthroughs in Dyadic Communications

Julia M Di Stefano

 

This paper shows that viewing dyadic communication from the perspective of servomechanisms and system dynamics rather than the cybernetics perspective (see Richardson, 1991, 128) allows deeper insights into the complex process of human conversations.  Instead of viewing feedback from the cybernetic perspectives as the influence of input back on the output (Richardson, 128) we view dyadic communication as a closed system, with positive and negative feedback loops.  This point of view helps us to better understand how to use feedback to achieve one's communications goals.  A case study based on the short story The Revolt of Mother by Mary Wilkins Freeman, illustrates the reciprocal (not linear) nature of dyadic communication, and the role of breakdowns in revealing its structures. This analysis has implications for managers who engage in conversations in which they create, take care of, and initiate new commitments within an organization (Winograd and Flores, 1991, 151)

 

The Dynamics of Managing a Life Insurance Company

Andrew Doman, Maurice Glucksman, Nathaniel Mass, Michael Sasportes

 

This paper reports the finding of an internal McKinsey research and development project designed to test the value of applying System Dynamics thinking to the life insurance industry.  The aim was to understand better how management decisions and actions can affect the success or failure of a typical direct sales life company.  The study compared the evaluation over 20 yeas of two companies, Equitable Life and London Life.  Starting out in 1975 from virtually identical competitive positions, Equitable has become the U.K.'s most successful life company, while London Life was rescued by the AMP Society from near insolvency in 1989.
We found System Dynamics a powerful means of identifying which managerial actions had accounted for the extraordinary divergence of the two companies.  The lessons learned include many counter-intuitive insights that have relevance for any life company manager.  Through simulation we were able to isolate which management actions made the difference to long term performance.  In particular, we show how attempts exceed the maximum sustainable growth rate specific to any individual company can lock it into a slow but relentless spiral of decline, from which there is little hope of escape.  This growth ceiling can be quantified and we also identify a number of a long range early warnings signs.  Consequently, we believe that our conclusions are likely to change the way life companies are managed in the future.

 

Systems for Modeling and Simulating in Schools

Hans-Ulrich Donhoff

 

This paper wants to report about an approach to make German pupils familiar with the problem of system dynamics, to promote the comprehension of complex system, to teach them something like "thinking in networks".
To reach this aim we employed a tool for modeling and simulating, comparable with well-known systems as Ithink or POWERSIM, but able to run on simple PCs under MS-DOS.
Using this tool we have developed the following four units (the subject in parentheses):
-Ecosystem forest (ecological balance, biology)
-Flows of carbon dioxide (chemistry)
-Growth (mathematics)
-"Tycoon" (economy)
Two of these units, "forest" and "economy" are the basis of our research.  In 11 groups with 238 pupils we made pre-tests, video recording and final tests,
The results in the field "model thinking" were remarkably better then in a polite study, initiated two years ago, the semantic and the syntactic correctness of the models have increased as well.
This will be evaluation of several items, regarding the aspects
-prediction of behavior
-forms of presentation, and
-level of net structure.

 

Modeling Infrastructure Induced Development at National and Regional Levels

Donald R Drew

 

Infrastructure induced development is a process dominated by feedback in that it features the synthesis of demand and supply functions.  For the demand function, we are seeking the infrastructure improvement requirement to accommodate a certain socioeconomic need; for the supply function we want to know the level of service obtained for a certain infrastructure improvement.  The objectives of the project from which the paper is derived is to develop a methodology for generating models that can be used to by planners and decision makers as instrumentalities for making reliable estimates of the economic health and productivity benefits and of potential infrastructure investment, and for linking infrastructure investment, users benefits, and succeeding economics development to provide a basis for rational policy formation.  The results is a methodology that permits one to answer the question: What would be the economic impact A, the social impact B, the demographic impact C, and the land-use impact D, the environmental impact E, and the users benefits F over geographic scale G for an infrastructure investment H at time T?  The approach is illustrated at both the regional and national levels.

 

A System Dynamics Model to Evaluate Policies on Institutional Decentralization and Community Participation

Isaac Dyner, Antonio Quintero

 

The new Colombian construction makes heavy emphasis on issues related to decentralization and community participations.  It intends to incorporate in Government the appropriate social actors to accomplish more effective administration.
In this sense, definitions have to be made in relation to regional responsibilities in the area of Health, Education, Housing, Public Services, and Employment, in order to obtain the appropriate transferences of resources from the central Government to the communities.  Laws on these issues are now being discussed in Congress.
Preliminary results show how System Dynamics proves to be an appropriate methodology to evaluate resources needed, community participation and institutional performance.
The model developed may be used as a training tool to help community leaders to understand the complexities involved in the decentralization process.  The model incorporates behavioral patterns and at the same time provides system performance and effectiveness indications (Community participation and accomplishments).

 

The Dynamics of Capacity Constrained Supply Chains

G N Evans, M M Naim

 

The analysis of capacity levels and there location is of vital importance in the design and management of supply chains as it is commonly believed that capacity constraints exacerbate poor customer service levels.  The inventory and order Based Production Control System (IOBPCS), often associated with "real life" production control system, is used as "company" building blocks for the dynamic simulation of a supply chain.  Various combinations of capacity levels through the supply chain are implemented at each echelon in the form of a maximum order rate that can be placed on the production facilities.
A strategy of maintaining a record of unfilled orders (backlog) at the production facility highlights a number of notable dynamic characteristics over and above normal dynamics of an unconstrained IOBPCS.  There is an excess inventory build up even as production order backlog is being depleted.  This is simply dealt with by effectively re-engineering the total business via integrating the company's overall inventory control policy with production.  The new system is used to analyze the effect of capacity constraints within a three echelon one player supply chain.  The inclusion of a non-linearity into the system leads to improved dynamic performance in some designs for the step change in sales and capacity constraint levels tested, but this does not mean improved consumer levels.
The strategy examined to improve dynamic performance is the holistic setting of system parameters to improve the non-linear systems.  The future direction for research and ideas for further improvement are also presented, where the simulation results indicate the need to closely monitor appropriate system variables such as inventory levels, and to incorporate them within more robust decision rules.

 

Teaching System Dynamics to Teachers and Students in 8-12 Environment

Diana M Fisher

 

System Dynamics at the pre-college level, its time has come.  English teachers have sufficient comfort with technology.  Tools such as STELLA II and PowerSim have provided the broad-based language for communication and understanding.
A recently awarded 3 year National Science Foundation grant, CC-STADUS (Cross-Curricular System Thinking and Dynamics Using STELL), is training 165 high school math, science, and social studies teachers in system modeling using STELLA II.  Teachers develop some models within their curricular areas.  Then Cross-curricular teacher teams are formed to design at least one large model and develop curricular materials around the model so it can be used immediately in their classes.  The training is done by high school teachers and by speakers from industry who use modeling in their work.  The teacher participants are responsible for sharing their knowledge and expertise with other faculty and with students in their classes.
High school students are using systems concepts at various levels.  At lower levels (especially with "at-risk" students) the teacher demonstrates how a model is designed and students manipulate the model and predict new behavior.  At the middle level, students develop a model as a class activity under the direct guidance of the teacher.  At the highest level, students select a topic of interest, formulate boundaries, work with an information resource person, and work with a modeling resource person to develop a model and present it to a class.

 

Using System Dynamics Technology to Improve Planning and Budgeting for Higher Education: Results in Arizona and Houston, Texas

Carol Frances, Marshall Van Alstyne, Art Ashton, Thomas Hochstettler

 

System Dynamics wee used for the first time to improve planning and budgeting in American higher education with a pioneering project launched in 1990 by staff of the Arizona Board of Regents to help the state of Arizona anticipate and prepare to meet rapidly growing enrollment demand over a twenty-years planning horizon.  Then, the University of Houston System, building on the experience of Arizona, chose to use System Dynamics to help meet their goal of achieving greater diversity among their students and serve the higher education needs of a dramatically changing population in their metropolitan area.
Though system dynamics was developed close to forty years ago at MIT and has widely used industry, it is new to the higher education.  This paper first briefly describes the actual experiences of Arizona and Houston in developing and using the system dynamics models for planning purposes, and then highlights special features built into the models.

 

An Archetype for Holistic Problem solving

F J Garlick, W Wynn

 

This paper discusses the nature of generalized problems solving and its algorithmic-like properties.  In the systems literature problem solving is usually discussed in relation to its methodological setting - for example, SSM may legitimately be regarded as a problem solving scheme.  This paper explores what we believe to be the five basic cognitive elements or strategies involved in problem solving.  An examination of these five strategies then suggests a way of understanding why particular methodologies have powerful problem solving power, and why explicit use of these five strategies within a methodology will result in an increased problem solving potential.
Some of the ideas discussed here arose from studies into how knowledge engineers solved the problem of knowledge elicitation and representation.  These studies were illuminating since the most common situation seemed to be that no real underlying strategy was employed and that the activity in essence was based on the chance plus experience.  In other words when practitioners were asked what strategy they were using the most common answer was that they did not know but they could do it anyway.  This form of knowledge is often called Tacit Knowledge - that is the sort of knowledge where we know what to do, but have no clear idea as to explaining how we do it.

 

Mathematical Simulation Model for the Study of the Transmission Dynamics of the Leishmaniasis Under a Systemic Approach

Lilia N Gelvez Pinto, Zandy C Muskus M, Hugo H Andrade S, Gerardo Munoz M

 

This article presents a model in System Dynamics, for the control of the Leishmaniasis.  This proposal presents the interactions among the five subsystems that intervene in the transmission dynamics of the Leishmaniasis: insect population, human population, animal population, the environment and the control strategies.  The parasite, the transmission personage, is defined as the element that determines the relationship among the subsystems that determines the epidemiological cycle.  The indicated subsystems are separated at different levels and its dynamics is modeled through a set of 120 different equations involving the different reported parameters in the scientific literature.  The resulting model permits to simulate the transmission with and without controls and to observe the efficiency by applying of those control policies.  The simulation is performed using a home made software called EVOLUTION, in two different conditions: natural conditions or without controls and with controls, obtaining quantitative and qualitative results which were considered plausible by the experts.  The set conformed by the software and then model could be considered a valuable tool for epidemiology research.

 

How to Use System Dynamic to Create Your Own Future: A Case Study of Worldwide Oil and Gas Exploration Group

Peter J Genta, David P Kreutzer, Gregg Anderson, Rusty Hinote, Williams C Hood, Kim McMillan

 

This paper describes the work and experience gained by a team of senior managers using a systems thinking approach, to develop their own set of future scenarios, to support a realignment of strategy and the redesign of a worldwide exploration group of a major integrated oil company.  The opportunity for this experience arose from a need to assess the diminishing returns produced during several years of overseas exploration activity.  According to a recent article in the Wall Street Journal, the entire petroleum industry has increased its search for reserves overseas.  “...between 1988 and 1992, the world’s 234 largest publicly traded oil companies spent $157 billion on exploration and development overseas, 49% more than in the U.S.”, but diminishing results.  In 1990, the industry discovered 148 barrels of oil outside the US  for every 100 barrels it sold abroad; last year it added just 100 barrels of foreign reserves for ever 100 barrels sold, while the average cost of replacing crude surged 55% to $6.56 a barrel.
Against this backdrop, the senior manager used a systems thinking approach to brainstorm the factors influencing the dynamics of the world oil and gas industry.  From this process the group was able to develop a set of five distinctly different plausible futures that might develop.  To test their group mental model for consistency, they develop a causal model of the industry and discovered that their five different futures all could be explained by a common model.

 

Implementing AACSB Standards Through Feedback-Loop Planning

Nicholas C Georgantzas, Amy Hamilton, Nancy Drobnis

 

To maintain the standards set forth by the American Association of Collegiate Schools of Business (AACSB), one thing a business school (B-school) must do is to maintain a certain proportion of tenured faculty members to students.  The AACSB standards also affect the process of reviewing tenure track faculty members for promotion and tenure (P&T).  Typically, tenure faculty members are considered more committed to enhancing the reputation of a B-school and of the AACSB through research and publications.

This paper presents a system dynamics simulation model of the interrelationships among variables pertinent to hiring adjunct and tenure track B-school faculty.  An ad-hoc committee of administrators, faculty and students of a relatively small prestigious B-school met to evaluate the implication of AACSB standards and to consider the possible implications the school’s recent expansion history might have on these standards five years into the future.
An important concern underlying the modelling process is that having less than fifteen students in classes is preferable to students.  Smaller classes allow for more instructor-student interaction, so the student better understands what the instructor require and the instructor knows the student interaction, so the needs and skills.  Estimates of the growth and attrition rates of both students and faculty members affect administrative decisions on the number of adjunct and tenure track faculty to hire. Although the time a student spends in the B-school program varies depending on whether enrolled full-time or part-time, the student growth history, the student growth fraction and the student growth forecast are the variables that determine future student enrolment.
The model confirms that the inexorable nature of P&T evaluation process makes the often desired balanced growth in B-school faculty a physical impossibility.  Yet, the model’s computed scenarios, which corresponding to alternative future student enrollment and faculty growth rates, show how the proportion of tenured faculty to students may respond differentially to alternative growth strategies.  An important implication of the simulation results would require the B-school administration to consider both ratios in making hiring and firing decisions for the B-school to maintain the current AACSB accreditation status.

 

Intermediate Structure Economic Dynamics: The Television Industry

Nicholas C Georgantzas, Philip A Schmid, Mark D Walton

 

This paper describes a system dynamics simulation model of the interrelationship among firms competing in the entertainment industry.  The model integrates ideas from strategy design, organization design and new technology adoption to describe exactly how the diffusion process of new hardware and software technologies into the entertainment industry is changing the power and stability of syndication firms, the dynamic changes in the extant production capacity of TV networks, and the investment opportunity in basic cable network system operators.
The economic organization and regulation of TV networks broadcasting vary substantially from country to country, but having a mixture of public private enterprise placed under the supervision of a government agency is a common arrangement.  TV networks and affiliates in the United States represent a clear manifestation of government regulation.  The granting of licenses and promulgation of rules pertaining to cross-media ownership enabled independently owned affiliates to carry regularly scheduled programming produced by the networks or by outside contractors. Except for news and sports programs, TV networks currently do not participate significantly in the ownership of production.  Yet this situation has been changing through modification stemming form the financial interests and syndication rules presently in effect.
A team of managers and planners from a group of syndicators met to discuss current events and the changing structure of the entertainment industry.  Changes stem from the moves of major pay cable channels, TV networks, basic cable networks and system operators, each responding differentially to the diffusion of new signal-transmission technologies into their industry.  A broad discussion culminated into a system dynamics simulation model of the interrelationships among firms competing in the entertainment market.  The model produced new insights into the power and stability of syndication firms, the dynamic changes in the extant production capacity of TV networks, and the investment opportunities in basic cable and networks and cable system operators.

 

Lessons for System Dynamics Mentors in Schools

William Glass-Husain

 

This successful, large-scale introduction of system dynamics into education requires many supporting elements.  One important element is an institutional structure that supports school change.  A major part of such a structure needs to be the availability of expert system dynamics mentors to provide on-going training and support for teachers.
This support occurs on three tracks.  One track is relatively formal workshops and meetings spent cooperatively developing projects.  Another track is classroom observation and documentation.  The third track consists of encounters by the coffee machine, and consists of informal, brief conversations where the mentor and teachers can brainstorm ideas or confer on a current project.  These methods of on-going support are preferable to the more conventional format of short-term intense workshops, which research shows has little long-term effectiveness.
In this paper, the author discusses his experience a part of the System Dynamics Project in the Catalina Foothills School District (CFSD), located in Tucson, Arizona.  Specifically, the author has been a system dynamics mentor at Catalina Foothills School District (CFSD), since the fall of 1992.  As a mentor, the author works with administrators facilitating the use of system dynamics as a method of instruction.

 

The Price of Oil: A System Dynamic Approach

J V Greenman

 

There has recently been a revival of interest in the dynamics of the oil market, not least because its key determinants are still a matter of intense debate even though the turbulence experienced in the 1970s and the early 1980s has largely dissipated.  One aspect of the discussion is how to appropriately model the market given that dominant paradigm of the 1970s - that of exhaustion of a finite resource - is no longer seen to be valid for the short time scales involved.  Models that are based on the behavioral simulation approach typically use the target-capacity utilization (TCU) supply-side model in their description of events, but doubts remain as to the validity of the TCU hypothesis.  In this paper we adopt a bottom up approach by modelling as closely as possible, from first principles, the strategies adopted by OPEC in their attempt to manage the world oil market.  We also look afresh at the demand side of the oil market to capture the completed lag structures that characterized the response to price volatility.  The complete model, constructed in Stella, is shown to reproduce accurately the hysteresis effect exhibited by the oil market in the period of interest.

 

The Management of Innovation in International Corporations as a Dynamic Process of Organizational Learning

Martin Grossmann

 

Scholarly research has long identified innovations as one important reason for internationalizing corporate business.  This statement is represented analytically by cause and effect relations at the beginning of the project. Innovations, i.e. the underlying technologies have a crucial impact on industries and their development over time.  The dynamic relationship between technologies and their industries will be explained on the basis of technology and industry life cycles. 
Subsequently, it is pointed out that one important precondition for generating innovations successfully is the organizational structure by which research and development (R&D) units are linked together.  Basically, three organizational models which are examined can be distinguished: an international network models, the process of organizational learning on knowledge, relevant for innovations, takes place in different ways.   To generate successful innovations, R&D personnel has to learn diligently and quickly from both: the new technological developments and from new or diligently and quickly from both: the new technological developments and from new or changing market needs.  Proposals could be made to facilitate organizational learning in the field of R&D.  Then, the organizational models are allocated to the quadrants of a technology portfolio.  One axis symbolizes the attractiveness of the technology which basically illustrates the technology life cycle.  This may offer a theoretical explanation of the need for adjusting organizational R&D models and the organizational learning process according to the dynamics of technologies.

 

Functional Economic Analysis of Purchasing at MITRE

Thomas Gulledge, Henry Neimeier

 

Functional economic analysis is a modeling approach that provides a uniform basis for analysis and comparison of alternative investment and management practices.  The approach takes into account the costs, benefits, and risks associated with new ways of doing business and managing organizations.  The entire purchasing process from initial request to final delivery, payment and accounting is being re engineered at MITRE.  A complete resourced process flow chart was developed for both the present and proposed systems.  An "i think" system dynamics model of both the present and proposed process was developed.  The model projects the seasonal workload over the proposed system lifetime.  Dynamic normal, overtime, and temporary staffing requirements were calculated.  The new system reduced total requisition delay by a factor of ten.  This will greatly reduced expediting actions and costs.  Multiple data bases and computer systems along the process were combined into a single system.  This greatly reduces data entry and reconciliation effort.  The new process groups purchase requisitions by type that provides the opportunity for bulk discounts.  All these will result in 37 million dollars of saving over a ten year system life.

 

Organizational Learning and Adapting Trajectories Found in a System Dynamic Based Business Game

Roger I Hall

 

The counterintuitive associations, known as Bowman's Paradox, found between measures of financial risk and return for a large sample of companies across many industries have previously been explained in terms of the attitudes of managers to risk using prospect Theory.  Similar results were obtained by the author from teams playing a system Dynamics based business game to stimulate a magazine publishing industry.  Experimental results of the dynamics movements of the team companies within the financial measures of risk and return space are presented.  Explanations based on organizational learning and adapting group decision making behavior provide an alternative account of the archetypal team transitions observed.

 

System Dynamics Underwood

Kjell Henden

 

This paper deals with System Dynamics as an alternative to methods of problem-solving that are traditionally taught in colleges.  It is based on my experience of teaching the use of the methodology for analyzing small system of finance, hydrography, demography etc.
Testing out any hypothesis where System Dynamics is compared to another methodology is complicated, and I do not present any conclusions.  I argue further that this has to be done by a qualitative approach.
In the field of finance quite a lot can be gained by using System Dynamics.  The given example of calculating the net present value of a cash flow illuminates my point.  In traditional textbooks this value is given by a formula based on the assumptions that interest remains constant over a long period of time, and that there is no or constant depletion of money value due to inflation.  In view of economic reality this description is very native.  On the other hand, it is rather cumbersome to develop and use a formula that takes in account variation of annual earnings, varying interest and varying inflation.  Similar observations have been my incentive for applying System Dynamics to various sciences.  Quite a lot of traditional calculations can be greatly simplified by resorting to the methodology of system dynamics; especially when it comes to integrating complex, realistic assumptions into the models.
My preliminary conclusion is that System Dynamics enhance the understanding and enables the students to go well beyond the oversimplifications of traditional textbooks, and that the use of the methodology in various disciplines should be advocated.  It is further my belief that teaching the subjects in undergraduate classes creates an underwood of users; a basis from which further system analysts can be recruited.

 

Competitive Simulations: Introducing Corporations to Organizational Learning

Gregory Hennessy

 

System Dynamicists usually view simulation as a means to help them understand the counter-intuitive behaviors commonly exhibited by complex systems and to facilitate others’ learning about these behaviors. However, a second and closely-related application is typically overlooked: the elicitation of barriers to organizational learning in a non-threatening environment. In our experience, when clients are placed on teams and presented with a simulated future, the organizational defensive routines which prevent effective decision-making in the real world soon arise in the simulation setting. A skilled facilitator can then begin to address these behavior patterns in the (relatively) safe context of the simulation.

Thus, we see tremendous power in the integration of the applications of simulation technology. First, the dynamic model used to build a simulation helps both the modeler and the client understand systemic behavior – which leads to better strategic choices. Second, the addressing of organizational defensive routines promotes learning and the conversion of such choices into timely action.

 

DIAGNOST; A Microworld in the Healthcare for Elderly People

Gerton Heyne, Jac L Geurts, Juliette Vermaas

 

DIAGNOST is a policy exercise based on a gaming/simulation in which managers and directors of institutions for the care of the elderly in a region of the Netherlands are given the opportunity to anticipate the coming changes in health care in general and in the care of the elderly in particular.  A microworld is created in which the participants can safely experiment with various policy options.  This paper describes the methods by which the game was constructed.  Apart from the more of less customary gaming techniques, also system analysis and tools from participative model building are used.  The results of the test runs and of the first official run are viewed and evaluated along with the methods and techniques applied during construction.

 

Launching System Dynamics

James H Hines, Dewey W Johnson

 

It is increasingly common for companies to undertake a system dynamics study with the aid of outside consultants.  However, it is still uncommon for even large companies to successfully bring system dynamics into the organization as an internal competency.  This paper reports on the efforts at Eastman Chemical Company to create an internal capacity in system dynamics.  At this point, Eastman has successfully launched system dynamics as an organizational approach to decisions making, and the effort continues to develop rapidly.  Eastman managers must yet address issues of sustainability, however the process that resulted in a successful organizational start is of interest in itself and may help other companies seeking competency in system dynamics.  This paper describes the launch of system dynamics at Eastman.

 

Modeling the Constraints on the Global Pharmaceutical Industry

Geoffrey D Hobbs, Bryan R Deane

 

Advances in all fields of medical technology have driven rapidly growing expectations of medical care over the last half century.  The rate of growth of this demand for health-care had consistently exceeded GDP growth and, in many countries, the health-care bill had been absorbing an ever greater proportion of government spending.  Governments throughout the world are increasing concerned that this growth is unsustainable.  The pharmaceutical industry, whose products account for about 5 to 10% of the health-care spend, has based on a cycle of growing sales from ever more effective new products, fuelling a substantial re-investment in high-risk, long-term research and development, leading to further advances and new product introductions.  Historically the overall sales growth has been founded on both price-related factors.

The purpose of this study was to explore the relevance of a System Dyna