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AbstractIn this section the System Dynamics Review presents problems having the potential to stimulate system dynamics research. Articles may address real‐world dynamic problems that could be approached fruitfully from the system dynamics perspective, or methodological problems affecting the field. A paper submitted to the Research Problems section should concisely motivate and define a problem and start a process of conceptualization or formulation that can open the way for further studies.

AbstractFounded in the mid‐1950s, the field of system dynamics has intellectual roots reaching much further into the past. The Archives section of the Review seeks to publish material from that past which can contribute to current theory and practice. The section welcomes previously unpublished but deserving system dynamics work, classics from past system dynamics literature that should receive renewed attention, and previously published articles from other disciplines of particular significance to current system dynamicists. Contributions emphasizing the philosophy and theory of model building, validation, implementation, education, and generic structures are particularly encouraged. Submissions may range in length from notes to main articles but may be edited. Send suggested material, together with a brief introduction placing it in historical and current contexts, to John D. Sterman, System Dynamics Group, M.I.T. E40‐294, Cambridge, MA 02139, U.S.A.

AbstractOngoing research at the Rockefeller College of Public Affairs and Policy is focusing on strategies for efficient and effective model building in groups. The intent is to involve a relatively large client group in the business of model formulation. Recent projects have explored strategies for accelerated group model building in the context of three public policy problem areas: foster care in New York State, Medicaid costs in the state of Vermont, and homelessness policy initiatives in New York City.Five roles appear to be essential to support effective group model building: the facilitator, the modeler/ reflector, the process coach, the recorder, and the gate keeper. This article identifies the five roles, briefly discusses the problem areas, sketches the design of the group model‐building efforts, and hypothesizes principles and strategies to guide future group model building.

AbstractNotes and Insights is a forum for discussion and debate about current issues in the philosophy and application of the system dynamics approach, and a marketplace for the exchange of information about current research, policy issues, and teaching experiences. Manuscripts treating material particularly suited to presentation in short form (less than 2,000 words) should be sent to Erich Zahn, Betriebswirtschaft‐liches Institut, Abt. IV, Universität Stuttgart, Keplerstr. 17, D‐7000 Stuttgart 1, F.R.G.

AbstractThis research explores opinions about best practices in system dynamics modeling elicited from a distinguished group of experts in the field. We address three questions: What do practitioners believe is the best way to undertake system dynamics modeling? What specific core activities are essential for exemplary action during the different stages of the modeling process? What do experts believe are the most important practices during the different stages of the modeling process? The researchers used a multi‐method approach involving interviews, virtual meetings using the Internet, statistical analysis of the generated data and, finally, a facilitated face‐to‐face meeting in which experts discussed the results of the study and their implications. The results of this research include 72 best practices grouped into six categories that reflect the stages of the system dynamics modeling process. Copyright © 2013 System Dynamics Society.

AbstractPublic policies often fail to achieve their intended result because of the complexity of both the environment and the policy‐making process. In this article, we review the benefits of using small system dynamics models to address public policy questions. First we discuss the main difficulties inherent in the public policy‐making process. Then, we discuss how small system dynamics models can address policy‐making difficulties by examining two promising examples: the first in the domain of urban planning and the second in the domain of social welfare. These examples show how small models can yield accessible, insightful lessons for policy making stemming from the endogenous and aggregate perspective of system dynamics modeling and simulation. Copyright © 2010 System Dynamics Society.

AbstractThis article briefly defines and describes the pathway participation metric (PPM), a mathematical calculation that can help to identify the linkages between the structure and behavior of a dynamic system. PPM has been implemented in an experimental piece of software called Digest, which we then present. Digest is not a simulation language, but rather a companion to any commercial system dynamics package, which accepts a text version of a simulation model and performs post formulation analysis of the model. Digest detects and displays which feedback loops are most influential in explaining a selected pattern of behavior in a model. Output from a sample Digest run is presented and described. Copyright © 2004 John Wiley & Sons, Ltd.

AbstractThis article describes a model of the life cycle of the petroleum resource in the United States. Expanding on prior system dynamic models of petroleum resources, the model endogenously generates the complete life cycle of the resource. It treats endogenously petroleum demand; the development of technology for, and investment in, exploration and recovery; discovery and production of petroleum; and the development of petroleum substitutes. With only two exogenous variables, GNP and the international petroleum price, the model portrays the evolution of the U.S. petroleum resource, and the associated industry, starting in 1870. The correspondence between simulated and actual data is examined through a variety of statistical measures. The model is used to show how the interaction between technological progress, depletion, imports, and the development of substitutes creates the life cycle by altering the dominance of the feedback processes in the system.

AbstractIn this section the System Dynamics Review presents problems having the potential to stimulate system dynamics research. Articles may address real‐world dynamic problems that could be approached fruitfully from the system dynamics perspective, or methodological problems affecting the field. A paper submitted to the Research Problems section should concisely motivate and define a problem and start a process of conceptualization or formulation that can open the way for further studies. Manuscripts not exceeding 2,000 words should be sent to George P. Richardson, Milne 308, Rockefeller College, S.U.N.Y., Albany, NY 12222, U.S.A.

AbstractThis note intends to contribute to the practice of group model building by presenting group model‐building scripts that can (1) create a preliminary problem boundary using less than one hour of group time, (2) convene discussions with the group that explicitly link dynamic structure with system behaviour, and (3) allow participants to "zoom" between a micro and a macro view of system structure. These scripts may be used during early phases of problem structuring. They build on an extended program of inquiry dating back to the Stirling System Dynamics Conference of 1994, and they utilize a well‐established group decision support system to facilitate group discussion, negotiation, and decision. Copyright © 2010 John Wiley & Sons, Ltd.