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System Dynamics

Volume 22 – Number 4        October 2009

Page 1, 2, 3, 4, 5, 6, 7

Session Reports - Tuesday

TUE 11:00 AM Parallel - Environmental Modeling and Communication

Synopsis: Ines Winz presented A System dynamics simulation that models the accumulation of the urban non-point source pollutant zinc from stormwater run-off into an estuary in West Auckland, New Zealand, by Ines Winz and Gary Brierley. Burak Gunerlap presented Dynamic interactions of socio-economic and biophysical systems for the Pearl River Delta in South China, by Burak Gunerlap, Michael Reilly, and Karen Seto.
Thomas Lowry presented Visualizing Spatial and Temporal Dynamics in Google Earth using Powersim, by Thomas Lowry and Robert Taylor). The session on Environmental Modeling and Communication, chaired by Gloria Pérez Salazar, went without a hitch at the eleven o’clock time slot.

Those of you looking for a professional review may be disappointed or possibly interested in what a soon-to-be undergrad with a BS in Environmental Studies sees in system dynamics. The three presentations observed and portrayed in this brief report had many common threads. Having been recently exposed to both of the main tools used by these researchers, which are Geographic Information Systems (GIS) and System Dynamics (SD), this reporter can testify to their tremendous value and benefits to society. What an awesome combination: system dynamics, with its ability to model over time, and GIS, that allows viewers to see locations from almost unlimited viewpoints and breakdowns.

Full Report

Lyle A. Davis

TUE 11:00 AM Parallel - Operations Management and Supply Chains

Synopsis: Three diverse topical researches related to supply chains were presented in the Operations Management and Supply Chains parallel session.

The first presentation, Using System Dynamics to Evaluate a Push-Pull Inventory Optimization Strategy for Multi-Tier, Multi-Channel Supply Chains, was specific to the government-owned defence sector, which faces demand volatility and supply uncertainties for their long production lead-time products. Creation of a push-pull boundary in the manufacturing supply chain and evaluation of the supply chain performance when optimal safety stocks are in place was demonstrated for the ten key components of a helicopter rotor blade. Through the use of optimization software and simulation through system dynamics models, it was possible to reduce the production lead time considerably. Further, the results also specified significant improvement in the recoverability of the supply chain when subjected to a sudden increase in demand.

The second topic, Psychological Safety and Group Learning: Cycle-Time Reduction for Collaborative Product Development, analysed collaborative product development in a manufacturer-supplier dyad. As a pilot project for the Taiwan high-tech electronics manufacturer and its tooling supplier, the vertical product development partnership is studied. The system dynamics inquiry helps inter-organizational project teams understand how cognitive and social factors such as psychological safety, level of collaboration, and group learning affect the development cycle-time more than technical factors such as the deployment of collaboration software.

The third topic, From Waste to Value - A System Dynamics Model for Strategic Decision Making in Closed-Loop Supply Chains, uses system dynamics models for strategic decision-making in closed loop supply chain (CLSCs). Original Equipment Manufacturers (OEMs), due to shortening product lifecycles and legislative regulations, face the challenge of handling products at their end-of-use or end-of-life and need to deal with questions arising from activities like collection, inspection, remanufacturing, or materials recycling. While process-oriented OEMS deal with decisions on appropriate collection, inspection and remanufacturing capacities, product-oriented OEMS have to extend it to B2B and B2C products. The simulation experiments conducted establish the economic potential of an engagement in value recovery activities and at the same time highlight the high complexity and connectivity inherited with various value recovery processes.

Full Report

Saroj Koul

TUE 11:00 AM Parallel - Design and Evaluation of Participatory Methods

The session was chaired by Etiënne Rouwette.

Allyson Beall and Andy Ford presented a comparison of a number of participatory environmental system dynamics case studies using a variety of modeling techniques. Models were determined successful based on their usefulness in helping groups view problems more holistically and their usefulness as decision support. Beall and Ford found that using system dynamics modeling with facilitation in the participatory process changes mind frames and improves civility. They recommend that modelers get everyone’s values early on and model the problem at various stages during the process.

Marjan van den Belt presented modeling techniques for integrating visioning, tools, and implementation at the ecologic scale using multiple (MIMSAS) data sources. She discussed modeling at various levels from stakeholder participatory to narrow research/science focus for adaptive management. Multi-level modeling helps assure vertical integration of scoping (individualization, local community, provincial/state, national, and global) so that all stakeholders see that their concerns are considered in the final decision-making process.

Mihaela Tabacaru, Birgit Kopainsky, Agata Sawicka, and Krystyna Stave presented their work on assessing the effectiveness of using simulation models to improve understanding of a system. They found that repeated iterative interaction with the model improved the learner’s performance in the four steps of problem solving: identifying cues and relevant aspects, formulating expectation/causal relationships, defining goals, and designing possible actions/decisions. 

Jake Jacobson

TUE 11:00 AM Parallel - Modeling of the Electric Power Sector

Synopsis: The session was chaired by Khalid Saeed.

System Dynamics and Laboratory Experiments, by Santiago Arango, Yris Olaya, Jaime Andrés Castaneda Acevedo

Santiago Arango presented a survey of system dynamics laboratory studies that were conducted by other researchers.  The studies focused on determining decision rules by observing behavior as subjects pursued prescribed goals in systems designed by experimenters.  System dynamics can improve the validity of experimental systems.

A system dynamics model for the German electricity market - model development and application, by Tobias Jaeger, Susanne Schmidt, Ute Karl

Tobias Jeager presented an overview of the development and validation of a model for the German electricity market.  The model leveraged prior work in the Zertsim model and made the model more specific to Germany.  As part of development, the team determined key factors influencing electricity prices and reduction of CO2 emissions.

A System Dynamics Model of the Mauritian Power Sector, by Kailash Balnac, Chandradeo Bokhoree, Prakash Deenapanray, Andrea Bassi

Andrea Bassi described the process of building a system dynamics model of the Mauritian power sector.  Mauritius is one of the most successful economies in Africa and they are currently planning a long-term sustainable energy policy to meet the additional demands that continued growth will bring.  Using Threshold-21 (T21) models as a base, an initial model of the power sector was developed to facilitate policy making.

Full Report

Michael Smith

TUE 11:00 AM Parallel - Planning and Routine Following in Strategy

Synopsis: This session was chaired by Kim Warren

Key performance indicators in professional service firms - a dynamic perspective, by Oliver Grasl

This paper takes a holistic approach to analysing the performance of a particular professional service firm based on the time senior staff allocates to the following tasks: project acquisition and delivery, contact and customer maintenance, service innovation and development and hiring junior staff.

Oliver Grasl
Scott Rockart
Susan Howick

Decision Rules and Organizational Dynamics, by Scott Rockart, Shayne Gary, Elena Vidal

A system dynamics model of magazine operations (based on Hall (1976)) is made to evaluate how fully differences in decision rules of German consumer magazines explain differences in firm dynamics. By taking rich models based on case studies of individual organizations, the authors expect to be able to generalize these models to explain the varied dynamics of entire populations of organizations. 

Supporting Strategic Conversations: The Significance of the Model Building Process, by Susan Howick, Colin Eden

This paper reports on the use of both qualitative modelling and quantitative system dynamics simulation modelling for a strategy making process in a UK police force. The strategic conversation that took place was facilitated by 2 modellers - one focusing on managing the strategic enquiry, while the other considered the implications of the conversation for the system dynamics model.

Full Report

Kim van Oorschot

TUE 2:00 PM Parallel - Dynamic Policy Analyses in Construction and Service Industries

This session was chaired by: Brian Dangerfield. Three different presentations took place. There were about 20 people in attendance who contributed positively with the three presenters.

The first presentation was titled Application of System Dynamics to Unsealed Road Maintenance Management, presented by Keith Linard. The paper discussed a system dynamics based pavement management model in Australia.

The second presentation was titled Application of Strategy Dynamics: Starbucks Corporation, by Pascal Gambardella. It was a strategy analysis of Starbucks Corporation using strategy dynamics. It showed the usefulness of this approach in addressing business performance issues for a real-world company.

The third and last presentation was titled Is Japanese Manufacturing Style (so-called Monozukuri) really robust? - A Causal Loop Diagram and Modeling Approach, presented by Shiro Fukushima. Some of the questions were answered by Kaoru Yamaguchi. Monozukuri (Japanese Manufacturing Style) is said to be one of the specialties of Japan. The Monozukuri model is developed by unifying various elements which have been conventionally argued in various academic areas.

Time was provided for each presenter as well as time at the end for questions from the attendees.

Ahmed El-Tagy

TUE 2:00 PM Parallel - Pedagogy Research - Improving Dynamic Thinking

Chaired by James Lyneis

Stock it to Me: Do System Dynamics Courses Improve People’s Understanding of Accumulation? by John Sterman
Sterman presented a newly titled examination of the widespread misunderstanding of the principles of accumulation (stocks and flows), even among highly educated adults trained in Science, Technology, Engineering, and Mathematic. He reported on an experiment with graduate students at the MIT Sloan School of Management to assess the impact of an introductory system dynamics course on their intuitive understanding of accumulation using a pretest-treatment-posttest design, in which the treatment consisted of the standard course content. Results show improvement in overall performance and a reduction in the prevalence of the correlation heuristic. A modest exposure to stocks and flows improves intuitive understanding of these concepts, at least at MIT, but the question remains about how durable the improvements will be. Will they be transferred to naturalistic settings and how quickly and well might others learn, for example children and the general population? In response to the question of whether prior experience by students or hands-on experience was important, Professor Sterman quipped that it was clear that his lectures alone had no impact. Asked whether gender makes a difference, the study indicated that some effect was at work, but it might relate to factors other than gender.

Does a Better Understanding of Accumulation Indeed Predict A Higher Performance in Stock and Flow Management? by Jürgen Strohhecker
Strohhecker pointed out that the stock and flow management (SFM) problem is of high relevance for a broad range of decision makers in society, business and personal affairs. He tested ability in understanding stock and flow management using three examples, and found that the performance of 26 undergraduates was poor overall. Then study participants engaged in an inventory management game, and he was surprised to see that, overall, no positive correlation between ability in the systems thinking examples and success in the inventory game. Jürgen proposed that a more elaborate causal model, sketched out in his paper, is needed to understand this performance question and should be tested in future research. In response to a question, he agreed with Professor Sterman that academics alone cannot teach people to do better.

A Test of the Relative Effectiveness of Using Systems Simulations to Increase Student Understanding of Environmental Issues, by Heather Skaza
Skaza’s experiment tested the relative effect of using simulation models on systemic thinking in a college-level Introduction to Environmental Science class, the examples being population dynamics and carbon in the atmosphere, with mixed results. The experimental group, offered training, did better on some tasks than others, while the control group performed better on the climate change task. The researchers were unclear whether this is a result of the system simulations used in the interventions or the assessment techniques employed to study their effectiveness.

Don Robadue

TUE 2:00 PM Parallel - Renewable Energies and Energy Efficiency

Synopsis: Silvia Ulli-Beer chaired the session. The three papers presented looked at applications of system dynamics to the specific domain of energy and electricity with a specific sub-focus of renewable energy and energy efficiency. The first two models focused on one particular renewable energy technology, solar photovoltaics, (PV) while the third focused on energy efficiency. Nitin Joglekar began the session with a look at solar PV diffusion in California. His model drew heavily from existing work on diffusion as well as models for the electricity sector. In general, the work sought to study the debate of solar grid parity and assess the role of a tipping point for solar PV diffusion. The second work, by Charles Jones, contrasted sharply with the first in terms of approach. Rather than drawing from the existing literature base, the work looked at solar PV diffusion in Massachusetts through the use of a grounded theory methodology and subsequent development of a diffusion model. Regardless, there were several parallels in structure and policy implications of the two models. The third and final model looked to apply the Threshold 21 framework for integrated modeling of energy, economy, society, and environment to the case of South Africa in order to look at policy implications for the country’s energy future. The work presented preliminary results from the development of the energy sub-model. In comparing nuclear versus energy efficiency policies, the latter was found superior in meeting the country’s energy objectives, especially in the short term.

Full Report

Katherine Dykes

TUE 2:00 PM - Special Summary of Energy Dynamics Thread

Synopsis: Quo Vadis, Dynamic Energy Modeling?

The topic of Energy and Resources has been subject of System Dynamics modeling exercises since the field’s inception. The world modeling project by Forrester in the 1970s was the major originator of a successful succession of energy dynamics modeling work. In the plenary presentation A History of Making Energy Policy, George Backus, from Sandia National Laboratories, pointed out that the system dynamics model FOSSIL2/IDEAS was the U.S. National Energy Policy Model from 1978 through 1995 and beyond.

Considering the long success story of system dynamics models informing strategic energy planning and policy analysis, system dynamics modelers interested in energy dynamics face a rich body of knowledge on which they can build their own modeling projects.

As chair of the Energy and Resources thread, I read submitted proposals and tried to develop a sense of the research frontiers the research papers are trying to expand. In the following, I am going to share some of my preliminary reflections on identifying the research frontiers in the Energy and Resources thread of the System Dynamics Society and the challenge of deploying the accumulated body of knowledge concerning energy dynamics modeling.

Coal fueled the Industrial Revolution, forever changing the way people would live and utilize energy. While this propelled human progress to extraordinary levels, the change came with extraordinary costs to our environment and, ultimately, to the health of all living things. It would not be until the mid-twentieth century that people would begin to understand the need to change our energy policies. Photo: University of Ireland, Galway -Paraphrased from here.


The Solar Two demonstration power plant, built by the US Department of Energy. Photo from here.

Full Report

Silvia Ulli-Beer

TUE 2:00 PM Parallel - Public Policy and the Environment

Synopsis: Three diverse topics related to the topical sustainability agenda were presented in the “Public Policy and the Environment” parallel session. Sustainability challenges are prevailing in many sectors and across wide ranging disciplines.

The first topic, Mental Models in Urban Stormwater Management presented the use of system dynamic modelling for the storm water management systems with inputs from 31 diverse stakeholders of the Twin-Streams catchment at Auckland, New Zealand. The authors, through cognitive mapping, have captured the perceptions on storm water problems and provided solution strategies in storm water management techniques. In order to realise sustainable storm water management, stakeholders need to focus on social learning, behaviour change, the creation of effective partnerships with local authorities and community ownership.

The second topic, The Change in Residents’ Participative Behaviour in Polluted Areas: a System Dynamics Perspective explored reasons for the declining public participation by residents of communities polluted with dioxin in southern Taiwan. The analysis of the behaviour captured through interviews revealed the unique nature of pollution victims the influence of an existing reinforcing feedback system. Policies to increase public participation were suggested.

The third presentation, Sustainability and System dynamics: some case studies, scrutinized the concept of sustainability and focused on the understanding of the system boundary conditions.

Through a few examples, the value of system dynamics view while formulating sustainability strategies was illustrated. It was found that while each example itself is a unique challenge, they share common threads: finite non-renewable resources, losses in renewable resource loops, and an economic system incapable of managing them sustainably.

In short the presentations conclude a better understanding of integrated systems for adaptive management, societal learning, and policies to manage transitions towards a more sustainable society.

The Chair Man-Hyung Lee, Professor, Department of Urban Engineering, Chungbuk National University, Korea is host to the 2010 system dynamics conference being held in Seoul, Korea

Full Report

Saroj Koul

TUE 2:00 PM Parallel - Industrial Policy

Synopsis: The session was opened at 2:00 PM in the Alvarado Ballroom with Cynthia Cavalli of Boeing Corporation as chair. It was attended by about thirty people. The first presentation was by Martin Kaggwa, the second by Sebastian Derwisch, and the third paper by Kawika Pierson.

Martin Kaggwa

Sebastian Derwisch

Kawika Pierson

Full Report

Deogratias Kibira

TUE 4:00 PM Plenary - Science and Technology

Synopsis: The Tuesday afternoon plenary session, chaired by David Ford, provided an overview of current efforts to use system dynamics and allied methodologies to improve the long range prospects for U.S. capabilities in Science, Technology, Engineering, and Mathematics (STEM). The session consisted of two papers: STEM Pressures from Birth to Globalization: Five Related Models, by Paul Newton (Presenter), Michael Richey, and Mohammad Mojtahedzadeh and Using System Dynamics to Model Student Interest in Science, Technology, Engineering, and Mathematics, by Hernando Sanchez, Brian Wells (Presenter), and Joanne Attridge. The first presentation provided an overview of a STEM problem, i.e., depletion of interest and capabilities in STEM while the nation faces an aging workforce. A comparative assessment of five modeling efforts that address various aspects of this problem was made. This was accompanied by a discussion of Boeing’s efforts in modeling the Rising before the Gathering Storm (RAGS) report. This work provides a context for framing other STEM efforts. The second paper described work done at Raytheon that used systems engineering methodology to examine various strategies for improving student interest and flow into US Colleges and eventually into STEM careers.

Full Report

Nitin R. Joglekar

TUE 5:00 PM Plenary - System Dynamics Society Applications Award

Synopsis: The System Dynamics Society Applications Award recognizes not necessarily an academic standard journal paper but any work that demonstrates or develops any application that is usable in the real world and has an appreciable effect on it. This year the award went to Mr. Gregory Lee and Mr. Kenneth Cooper from Fluor Corporation, for developing the Change Impact Assessment tool. The tool has been extensively applied to improve project management in the company with great success and uses system dynamics to simplify large, complex, capital intensive projects. The model is set up and tailored for every diverse engineering and construction project the company handles, including energy, industrial, commercial, infrastructure, and federal government projects. It is used to foresee the future cost and schedule impacts of project changes and events and, most importantly, test ways to avoid the impacts. The tool has been used in more then one-hundred projects so far and improves the understanding of the trade-off between costs and construction start and completion dates. The whole workforce at Fluor, from top to bottom, has been trained on how to use this model, and has given the company a significant advantage over its competitors.

From left to right: Greg Lee, Kim Warren, and Mr. Ken Cooper

Full Report

Kamal Qaiser

Session Reports - Wednesday

WED 9:00 AM Plenary - Modeling for Policy Formulation

This plenary session was chaired by Ed Anderson.

A History of Making Energy Policy by George Backus and Jeff Amlin
This was a session which not only exposed the audience to the vast amount of good system dynamics work which has been carried out in the energy domain, but also increased their understanding of what it is like to manage such inevitably large models in both a technical and a political sense.

George took the audience through a history of system dynamics models for energy policy from 1970 onwards. He described how COAL2 evolved into FOSSIL1, subsequently FOSSIL2 and ultimately ENERGY 2020. FOSSIL2, which had much to do with Roger Naill, was the de facto National Energy Policy model from 1978 until the early 1990’s. It covered all fuels and all sectors and had a strong influence on oil / gas deregulation in the USA as well as generating a rethink on the strength of commitment to nuclear energy.

ENERGY 2020 informed Canada’s stance at the Kyoto meeting: it brought energy policy to the regional level.

George volunteered some wisdom achieved through all these decades of energy policy modelling. He mentioned George Box’s often-cited comment that: “All models are wrong but some models are useful” (1987). He asked: “But how wrong are you prepared to be in order to be useful?” A model can be considered useful if it avoids the adoption of poor policies. He felt that ENERGY 2020 fell into this category: it was wrong, but useful. He further asserted that: “A model is a tool and is only as useful as the artist makes it.” Typically, energy policy models must be re-tailored for each individual client.

He asked us all to contemplate aspects of model validation. Which was the most important: fidelity; robustness; or prediction accuracy? Selective detail in a model is there not to improve any technical aspect of the model’s functionality but rather to increase the bond with the client constituency. ‘Successful’ models serve an unavoidable political function. Sometimes the model might support a future history – that which a policy-maker thinks is the right way forward. The model must be seen as part of the system: it must benefit an influential person who will champion these benefits to others.

Pandemic Influenza and Complex Adaptive Systems of Systems (CASoS) Engineering by Robert Glass
Robert, who works in the local Sandia National Laboratory, shared his time between a focus on influenza pandemics and other analogous complex adaptive systems.

His involvement with the H5N1 strain of influenza began about 4 years ago when he began adapting his complex system models, used to design power grids and to manage the movement of funds from one bank to another, to infectious diseases and influenza in particular. The models were characterised by many components and groups of components and were highlighted by reflecting cascades of activity.

Policy design in this area had analogies with fighting forest fires. If a discarded cigarette could cause potential wildfires, then the answer might be to build fire breaks. But an alternative policy might be to thin out the forest so that it didn’t matter as much. He pondered as to whether social networks might be ‘thinned out’ and influenza fought by focussing on local community networks and migration. Following a project on social networks which his young daughter had to complete as a school project, Robert became convinced that a social network model would be the best way forward. He determined that the backbone of infectious contacts hinged around kids and teens. If they were to be vaccinated there would be no epidemic. So he built a model based upon informal social influence networks which escalated through 4 degrees of separation.

He noted that those involved with setting public policy in this sphere were seemingly way off beam. Some influential people in the White House at the time felt that closing the borders was the answer! His team tried to influence a different public policy for this domain and submitted an account of their model to the journal Science. Some big names in epidemiology would have refereed the paper but the team didn’t get a reply.

Notwithstanding this setback they pressed ahead with their model of social networking and eventually they made a breakthrough when the Department of Homeland Security became convinced of its qualities and the result was a change in the course of public policy in this arena. Naturally they had lots of questions about the details of the model and most likely several millions of runs of it were conducted. But at the core of their concern was the central issue: what is the best influenza mitigation strategy? They wanted to know how robust possible policy combinations were to model assumptions. And what settings were required for policy choices to be most effective?  All results were evaluated and corroborated by the modelling team. The eventual outcome was that Interim Pre-Planning Guidance was published by the DHS in February 2007.

An interesting end-point on this talk was whether CASoS-type models were system dynamics models in the true sense of the word. To this reporter the model seem more in line with agent-based modelling, but John Sterman was quick to point out that the model was dynamic, broadly-based and contained feedback – and this characterised system dynamics. The debate continues!

Brian Dangerfield

WED 11:00 AM Parallel - Biofuels and Food Markets

Systems modeling and analysis for commercial pathways assessment of oil crop based biofuels in Hawaii presented by Stephen Conrad presented on behalf of his two co-authors.
The authors conducted a systems-level analysis of the commercialization potential for growing oilseeds and refining the oil into advanced biofuels. System dynamics models focusing on feedstock production and cost modeling were constructed to evaluate the economic potential for growing oilseeds such as macadamia nuts and palm oil at a commercial scale and refining the oil into renewable jet fuel and green diesel. Hawaii was used as an example of our commercialization analysis approach. If a case for commercialization can be made for one or more niche markets, those markets could serve as sites for improving production efficiencies and become “jumping-off points” for much more widespread commercialization. Important constraints were revealed: a co-product would be needed, since bio-fuel costs were $15 per gallon when $7 was needed to compete against the floor price of bunker fuel. Land cost and availability is another constraint, given that land owners are risk averse and that plantation agriculture is not a desired outcome in the case of Hawaii. Questions from the audience illustrated additional limits; for example, even a single viable standard production facility of 6,500 barrels per day would require more land area than Hawaii presently has available. Labor costs are another constraint, since oil palm must be harvested by hand.

Peak oil, biofuels, and long-term food security, by Erling Moxnes
The presenter took on the subject of whether biofuels could break oil dependency or lead us down a blind alley, since such fuels compete with food production. He uses a simulation model to study how markets for oil, biofuel, and food may interact and develop in the long run as world oil production peaks then starts to decline due to resource depletion. He hypothesizes that a shortage of oil will make biofuels highly profitable, leading to a take-off for the biofuel industry, and, in turn, to food shortages and starvation. The results of the model do not permit the authors to reject this hypothesis. They found that a number of policies all tend to delay rather than cure the problem of food shortage. Biofuel production should not be allowed to occur on lands suitable for food production; indeed, it seems urgent to start discussing and building support for a ban of such investments.

Renewable Energy: A Framework to Model a Brazilian Case of Success, presented by Joaquim Rocha dos Santos on behalf of his three co-authors.
The authors modeled the dynamic interplay of policy and implementation of the dramatic rise, fall, and resurgence of ethanol as an alternative fuel over the period 1970 to 2003. The 1973 oil crisis lead Brazil to experience economic problems, motivating the Proalcool program, which extended from 1979 to 1990, supporting the use of ethanol-only cars (E-100). After the program was terminated in 1990, a decline in international petroleum prices and an increase in international sugar prices lead to a shortage of ethanol, damaging confidence in ethanol and driving the purchase of ethanol cars to zero. The advent of bi-fuel automobile engines after 2003 has resolved the boom-bust cycle by allowing drivers to purchase whichever combination of gasoline and ethanol makes economic sense based on prevailing market conditions. As a result, in only three years, about eighty-five percent of all cars sold in Brazil now use this technology. This has caused a boom in the ethanol industry, which competes in terms of resources with the sugar industry.

Don Robadue

WED 11:00 AM Parallel - STEM Pressures from Birth to Globalization

Synopsis: Jac Vennix and Daniel Horschel chaired.
Workforce Modeling for the National Institutes of Health (NIH), by J. Chris White (presenter), Margaret Rush, and Dr. Walter Schaffer. Mr. White provided an overview of a project he is working on at NIH with Dr. Walter Schaffer regarding the NIH pool of funded Principal Investigators. The motivation for the project came from looking at the average age of funded investigators for NIH projects from 1980 to 2005... 

Full Report

J. Chris White

WED 11:00 AM Parallel - Public Policy for Large Systems

Tsuey-Ping Lee welcomed the audience and introduced the speakers for the session.

Anna Mayerthaler

Timothy Taylor

The first presentation was made by Timothy Taylor on a paper titled Science, engineering and technology in the policy process for natural systems. The paper was co-authored by David Ford, Shari Yvon-Lewis and Eric Lindquist, all from Texas, A&M. One of the main premises of this study is that Social and Natural Systems are linked, but policy makers have a limited understanding of these complex systems and their interactions. To further the understanding, these researchers built a system dynamics model to test and analyze of stratospheric ozone depletion and the follow up policy making and implementation process. Lead pollution was mentioned as another potential application to test and calibrate the model structure. Ozone, lead and now, Climate Change, require not only technology, but also the political will and actions. There is a time lag to policy development and implementation as well as several feedback loops. Among other things, the model integrates atmospheric chemistry and an understanding policy work – focus on the interaction between systems. Several feedback loops were presented and at some point in the model, the risk of emission regulation is mitigated by replacement technology. The conclusion was that research and technology development are important, but the link to policy makers and implementers needs to be made faster to achieve results faster. Timothy concluded with the question: “If you have one hour, is it better spent on 1 hour of research or calling your congressperson?” He also observed that the attention time of politicians should be better researched, because there is more data on atmospheric ozone than there is on decision-making response time, while the model seems to indicate that this is a major driver in curbing undesirable impacts on the natural environment. A member of the audience asked if this model could be applied to Climate Change and Timothy thought that the issue seems too complex. He also illustrated his point with a distinction based on Ford, 2007 and Claussen et al, 2002 to evaluate models on integration, detail and process.

The second presentation was by Nicolas C. Georgantzas, on a paper co-authored with Evangelos Katsamakas and Dominik Solowiej, from Fordham University in New York, NY and Stanislaw Staszic College of Public Administration. Nicolas presented the paper, titled Giddens Globalization: Exploring Dynamic Implications. The objective of their work was to develop a model to reflect on the dynamic processes that support or inhibit globalization, based on elements such as technology, institutional structures, beliefs and social behavior as posed by sociologist, Anthony Giddens. The discussion that followed was geared toward the fact that large scale models always leave space for adding more detailed feedback loops. However, this model was primarily constructed to better understand the thought dynamic processes of Giddens.

The final presentation was by Anna Mayerthaler, on a paper, A Land-Use/Transport interaction model for Austria”co-authored by colleagues Reinhard Haller and Guenter Emberger, all from the Vienna University of Technology, Austria. Anna skillfully presented an adaptation of the existing Metropolitan Activity Relocation Simulator (MARS) model and linked it to a dynamic land-use transport interaction (LUTI) model. Of interest are the structural changes in the model, as demonstrated by output maps that showed intensification of urbanization around existing urban areas in Austria. Questions were directed toward the “gravity model approach” that was used to estimate transport model and land-use parameters. This model used the built-in optimizer of Vensim and a comment was made that the optimizer increases internal model consistency, but doesn’t necessarily add to external validity of the model.

Marjan van den Belt

WED 11:00 AM Parallel - Security

Alexandra Medina- Borja

Jazir Radianti

Johannes Wiik

Understanding the Role of Victims' Non-Discretionary Factors in Hurricane Evacuation Dynamics, by Alexandra Medina-Borja, Yesenia Cruz, and Joaquín Medin Molina

Alexandra Medina presented an interesting paper exploring factors related to the attentions of the victims of a disaster by Disaster Relief Organizations (DROs). The paper establishes that prompt and effective response to either natural or man-made emergencies requires the analysis of key information where the role of disaster relief organizations is multiple. She presented a model based on the analysis of data collected from victims of the 2005 Katrina Hurricane and paired it with real operational data provided by the American Red Cross. She then calibrated/validated her data with real data from the 2005 Rita Hurricane. Such a model could help to determine in advance the emergency supplies and personnel required for a disaster relief operation.

A Quest for a Framework to Improve Software Security: Vulnerability Black Markets Scenario
by Jaziar Radianti, Jose Gonzalez, Eliot Rich 

The second paper was presented by Jazir Radianti and examined how a model draws on empirical observation on black markets and market-based approaches for vulnerability discovery to generate a simple model of vulnerability black markets (VBM). The model results suggest that efficient legal markets may attract malicious hackers to enter the legal markets and may reduce their likelihood involve themselves in vulnerability black markets. However, better patching management may mitigate the abuse of software vulnerabilities.

Chronic Workload Problems in CSIRTs, by Johannes Wiik, Jose Gonzalez, Pål Davidsen, and Klaus-Peter Kossakowski

Last, but not least, Johannes presented a paper focusing on low-priority incident response. He mentioned that this type of incident is growing exponentially, which overwhelms the limited CISRT resources of Computer Security Incident Response Teams (CSIRTs) who have been afflicted by chronic problems concerning workload, quality of service, and sustaining their constituency; the CSIRT tends to handle the workload by adjusting the productivity of manually handled incidents, a futile task owing to exponential growth in incidents. The authors concluded that a more fundamental solution is automated incident response, but its implementation requires careful planning of timing and resources.

Gloria Pérez Salazar

WED 11:00 AM Parallel: Pedagogy Research – Interactive Learning Environments

Capturing the Dynamics of a Psychiatric Illness: A System Dynamics Translation of the Contemporary Biological and Psychological Conceptualization of Panic Disorder, by David Wheat

The stated goals of Wheat’s work are to encourage teachers to use system dynamics translations for explanation of theories as well as build student note-taking skills and to encourage collaboration between psychology and system dynamics. The discussion focused on partial translation. System dynamics translation represents a narrative theory as a system dynamics model. The goals are to make explicit the dynamic processes implicit in the narrative theories of panic disorders in order to facilitate better understanding and provide a common language between psychology, biology, and other fields. Their research method translated panic disorder, in which heart rate serves as an indicator of fear, to make explicit the dynamic processes implicit in panic attacks.  

Exploratory Strategies for Simulation-based Learning about National Development, by Stephen Alessi

The stated goal of this work is to improve student learning of complex models by using system dynamics as a learning mechanism. To achieve this, researchers investigated instructional strategies for designing computer simulations and simulation-based games. The talk discussed two of these strategies: guided student exploration and non-guided student exploration (serving as experimental controls). Students with guided exploration of the system explored the system before consequential decision-making was used. The control group went directly into the decision-making phase. The guided exploration group produced better policy decisions and had better understanding of the problem than did the controls.

The Effectiveness of Force Directed Graphs vs. Causal Loop Diagrams: An Experimental Study, by William Schoenberg

William presented a pilot study to investigate the efficacy of Causal Loop Diagrams in comparison to Force Directed Graphs for decision-making. Six participants were assigned to either Causal Loop Diagrams or Force Directed Graphs to make decisions regarding possible ways to raise the per capita income of Blendia, a fictitious country, as high as possible. The results of the study were inconclusive. Force Directed Graph users did exhibit better strategies than the Causal Loop users. However, the Force Directed Graph users did not use these strategies to produce better decision-making. The discussion later focused on a future, larger study that would involve a larger number of participants and well as have methodological adjustments to the pilot study.

Michael Bernard

WED 11:00 AM Parallel - Environmental Modeling and Understanding

The first paper in the session was presented by Asmeret Bier from the School of Earth and Environmental Science, Washington State University. As part of her PhD project, Asmeret examined the role of thermal water quality trading programs. As part of these programs thermal point source polluters can offset their pollution by paying land owners to plant shade trees which can reduce water temperature and therefore increase water quality. The Riparian Shading Simulator explores effectiveness of policies with varying trading ratios and upstream-only rules on a hypothetical river. The stock and flow model consists of four sectors: hydrology, heat flows, shading and trading. All are explained in detail in the accompanying paper. Asmeret concluded that upstream-only rules can lead to adverse spatial concentration of high water temperature downstream. She also showed how the model can be used to trade-off costs associated with offsetting pollution and the environmental benefit gained from doing so.

Asmeret Bier

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Richard Dudley in discussion with colleagues

The second paper in the session was presentedby Richard Dudley. Richard introduced a simple model that looks at how different policies can reduce CO2 emissions from deforestation and forest degradation. These policies are currently being promoted for inclusion in future climate agreements. The model also includes a valuation of avoided emissions even though it is noted that this policy implementation is hard because of the uncertainty in measuring baseline deforestation rates. Furthermore, Richard compared scenarios and discussed possible feedback effects between CO2 offset availability, CO2 price and emissions reductions. Please note that Richard also included the Vensim model as supporting documentation. This can be downloaded from the online proceedings on the conference website.

Sondoss El Sawah from the University of New South Wales, Australia was the third speaker and presented insights from her PhD research on water management in the Australian Capital Territory (ACT). This watershed has experienced extremely low water storage levels in dams due to prolonged drought, bushfires and increasing consumer demand. Demand management is presented as sustainable long-term solution but its successfulness depends on effective communication. While Sondoss’ research is work in progress, she outlined a number of feedback loops that may emerge as important drivers of system behavior, particularly the role of re-growing trees who deplete subsurface and groundwater stores which leads to drier soil and therefore a potential increase in bushfires. It will be interesting to see whether these feedbacks can be validated as part of her quantitative model development.

Sondoss El Sawah

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Session Chair Allyson Beall with presenter Sondoss El Sawah

 Ines Winz

WED Noon Poster - Information Management Posters

Agile Project Management by Warren W. Tignor
Observing real life Scrum projects, Warren Tignor noticed that the tendency in these projects was to focus on new functionality in the next sprints rather than on errors and necessary rework. With Lyneis & Ford’s conceptual model for project management (2007) in mind, he examines how this generic structure applies to Agile project management. He concludes in his paper that Agile project management fits the system dynamics project management model. He also notices that the concepts of rework cycle, project control, ripple effects, and knock-on effects defined by Lyneis & Ford (2007) are recognized by the Agile community but not the synergy of their relationship. As a result, this is an area where Agile project management can benefit from system dynamics.

Elisabeth Andersson

WED NOON Poster - Military Applications

Synopsis: James Melhuish, a Lead Systems Engineer and Modeler at BAE Systems in Burlington, MA, presented CMIST for his team. CMIST is a custom development and modeling environment for creating and integrating simulation models to address high-level strategic decision-making using a variety of methodologies.  In an approach that borrows from Object-Oriented Design (OOD) and Model Driven Architecture (MDA), model classes are defined by the M&S Developer, or programmer, and instantiated by the Commander, or modeler. This allows for multi-level M&S paradigms to come together under one roof. The two basic parts are the development environment and the modeling environment.

The CMIST environment was built using the Eclipse framework, a widely used open source Java IDE. The model presented used three different paradigms:
1) Probabilistic cause-effect modeling enabled by dynamic Bayesian network algorithms from Air Force Research Laboratory’s Operational Assessment Tool (OAT)
2) System dynamics modeling enabled by U.C. Berkeley’s open source Ptolemy II
3) Agent-Based modeling enabled by Telecom Italia Lab’s open Java Agent Development (JADE) framework.

Full Report

Lou Mauro

WED 2:00 PM Discussant-type Session: Diffusion Dynamics

Synopsis: The session was chaired by Jim Duggan and was attended by approximately twenty persons.
The first paper titled Local Analysis of Individual-based Viral Dynamic Models with Eigenspace and Eigenvalue Elasticity Analysis was presented by Qian Zhang from Indiana University. This presentation was related to the complexity of infectious disease spread. A model of immune epidemiological dynamics was used in this work.

The second paper titled The Impact of Aggregation Assumptions and Social Network Structure on Diffusion Dynamics was presented by Gonenc Yűcel from Delft University of Technology.  This presentation challenged the assumptions regarding the aggregation and social network structure on diffusion dynamics. Results from a set of experiments were presented.

The presenters: Gonenc Yűcel and Qian Zhang

Full Report

Angelica Burbano

WED 2:00 PM Discussant-type Session: Housing and Banking Crisis

Synopsis: The first paper in this session, On modeling some essential dynamics of the subprime mortgage crisis, was presented by Lianjun An. All three authors are affiliated with IBM T.J. Watson Research Center in Yorktown, New York, USA.

The second paper in this session, Korean real estate market mechanisms and deregulation of mortgage loans: qualitative analysis, was presented by Sungjoo Hwang, MSc student at the Department of Architecture, Seoul National University. The other two co-authors, Moonseo Park and Hyun-Soo Lee, are Associate Professor and Professor of the same department and university, respectively.

This session was a newly introduced arrangement in which only two papers were presented in the traditional one hour slot for a parallel session. Under this new format, each of the two presenters was offered twenty minutes for the presentations followed by discussion sessions led by the chair of the session. The session was well attended.

Full Report

Mahtab Akhavan Farshchi

WED 2:00 PM Discussant-type Session: Health Applications

The two papers presented and discussed in this session were also the winners of the Lupina Foundation Award for young researchers. 

Evaluating the Effect of Integrated Health and Social Care Information Systems on Delayed Discharging of Patients, by Angeeta Sardiwal
The work defined flow processes for elderly patients in the UK’s National Health Service and addressed causes of delayed discharges. The model developed as part of the work revealed that implementation of information systems by themselves can make delays worse, needs to be accompanied by capacity increases in critical areas, and can help identify the need for resources such as district nurses. Next steps are to take this approach to other NHS Trusts and identify additional information to be included in integrated health and social care systems. 

A Simulation Model for Bloodcholesterol Dynamics and Related Disorders, by Emre Demirezen
The model describes the forces maintaining cholesterol balance in the human body, encompassing elements in the blood, liver, extra-hepatic tissue, and digestive system as well as body weight and diet and exercise. Emre described how the model was validated and tested with multiple scenarios including changes in diet and exercise and applied to particular cholesterol disorders such as familial hyperlipidemia. Next steps are to particularize the model more for individual characteristics and include the effects of stress. Comments included the fact that this is a useful framework for doing comparative effectiveness analysis on alternative treatments and that it would be good to adapt the model as a training simulator that would help people learn how to better manage cholesterol.

Gary Hirsch

WED 2:00 PM Discussant-type Session: Organizational Dynamics

Chaired by Brad Morrison. Discussant: Andjelka Kelic

Integration in cross-border mergers and acquisitions, by Abhijit Mandal, Aida Hajro

Although there has been continuing growth in acquisition-volume over many decades, there is little evidence of benefit to acquirers. Post-acquisition integration is an important generator of value, and it may range from no integration to full homogenization of the merged entity. This paper examined the role of norms, social identity, emotions, and reciprocity in obstructing the successful integration of acquired firms.

The discussion examined whether there may be errors in the perception of norms between acquired personnel and the acquirer, potentially creating problems that need not arise. One participant described a company that had made more than thirty acquisitions across five countries and had experienced little conflict in cultural norms. Thus, it questioned how widespread norm-conflict may be in practice. The phenomena may be present in within-country acquisitions, but be greater in cross-border cases.

-Could the problems be mitigated by looking not at the existing norms of the acquired firm, but at its aspirations?
-Could the issue be generalised to deal with any situation of imposed change, not limited only to acquisition cases?

Dynamics of escalation of commitment, by Özge Pala

The tendency to keep investing in a previously-chosen course of action, even after seeing negative performance, is thought to result from four groups of factors: tangible issues about the project itself, personal psychological factors, social factors, and organizational factors, the last three being intangible. The question is about the relative influence of each and how this may change over time. It has been thought that they change in priority, as the situation progresses, in the order above. Alternatively, they may operate in some aggregate manner. The experimental model allowed these questions to be tested in three situations: a good strategy, a bad strategy, and a mid-quality strategy. Commitment to the first can easily escalate, of course. Commitment to a poor strategy may build for a while, if poor performance is tolerated as being possibly short-term only, but ultimately dies.

Commitment dynamics to mid-quality strategies is more complex, reflecting such issues as a gap between actual and perceived performance. The work identified one clear practical recommendation – for teams to decide from the outset at what point (performance relative to investment) a project will be terminated.

Further questions:
-Whether ‘escalation’ is in fact the right term – most cases concern persistence of already-high commitment (except in some cases where individuals may actually become more committed in the face of attack)?
-What if performance itself changes over time (e.g. starts out looking good but then deteriorates)?
-How does commitment change in situations of numerous repeated projects?

Kim Warren

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