Mental health service systems are inherently complex, both in their detail and dynamics. System dynamics offers great potential to help policy makers, administrators, and researchers make better decisions about service system changes. However, efforts have been constrained by not being able to construct numerical reference modes without making strong assumptions about the structure of the case flows. This paper presents a novel approach to generating numerical reference modes from administrative databases that is based on computation theory. The method is validated with simulated datasets, and its feasibility and substantive significance demonstrated in an analysis of a merged child welfare database containing 10,250 children and adolescents.
Skilled human movement is apparently easily produced and highly coordinated despite the high number of degrees of freedom controlled during its execution. Here, we examine the learning of a whole body movement over practice from three levels of analysis: 1) elemental, 2) subsystem, and 3) macroscopic order parameter, with respect to the role of constraints in motor skill acquisition. With practice, the body segments were re-organized to achieve the 3 sub-tasks, namely: 1) a medio-lateral forcing torque, 2) a vertical downward force and 3) an anterior-posterior equilibrating torque. The output complexities of the two subsystems, the forcing (medio-lateral) and equilibrating (anterior-posterior) motions of the center of mass changed in a compensatory manner, increasing or maintaining the stability of the overt behavior. This pattern of findings supports the ideas of dynamical approaches to motor learning and holds interesting parallels to tenets of the Theory of Constraints (Goldratt, 1990) for system (re)organization.
The members of the Health Policy SIG agreed at the Oxford conference in 2004 to begin a collaborative effort to examine national health care system reform from an SD perspective. The first product of this collaboration is a paper being presented at one of this years parallel sessions, entitled Achieving health care reform in the United States: Toward a whole-system understanding. The paper includes a series of causal loop diagrams laying out an initial theory of why reform efforts have largely failed in the U.S. and outlining the characteristics of more effective reform. This paper was recently distributed to all HPSIG members for their comments, and also to some U.S. health system experts from outside SD. During the special Sunday afternoon session we will review the comments we have received and also hear directly from a few of the outside experts who are able to join us in person. We will also look to non-U.S. HPSIG members for an international perspective, and talk about how we can best expand our collaboration both internally and externally during the year to come.
Modeling assistance is available at the conference to enable modelers to discuss their specific modeling questions with modeling coaches. Modeling assistance opportunities include two public workshops, as well as the possibility of assistance at any time during the conference. Assistance is available for modelers with all levels of modeling ability, from beginner to advanced, with questions about a specific model that modelers are developing or studying, or to better understand something in a book, an article, or a software package. Modeling questions may deal with problem articulation, formulation of a dynamic hypothesis, formulation of a simulation model, model testing, or policy design and evaluation. Modelers should bring whatever materials they need to describe their question,including pencil and paper, books, posters, or laptop computers. Spectators are welcome to observe modeling assistance during the two public sessions.
The Global Systems Simulator addresses the issues of sustainability and carrying capacity at a global scale - the same issues addressed by the Jay Forrester's World model. The current version of the GSS is a prototype intended as proof of concept for a much different approach to modeling. Systems models are seen as explicit extensions of the mental models we use to interpret the signals received by our sensory apparatus and to navigate in the real world - extensions that enable us to perceive the long term and systemic consequences of potential actions. The approach has its roots in the activity analysis of Koopmans, Leontief, and Georgescu-Roegan, the system dynamics of Forrester, the control theory of Mesarovic, the general system theory of Weiner and Laszlo, the principle of uncertainty of Prigogine, and the cognitive theory of Bateson, Maturana and Varella. The GSS is implemented using the whatIf? software technology, a platform developed by Robbert Associates for large scale simulation modeling. The workshop will demonstrate these concepts using the Global Systems Simulator.
Hsinchu Science Park is an example of hi-technology industry development in Taiwan. Its rapid growth has brought tremendous economic benefits, though not without social and environmental impacts, resulting in conflict between economic growth and sustainable development of the science city. This study establishes a system dynamic model using STELLA programming language to simulate different development scenarios of Hsinchu Science City. Our analysis reveals that the development of the science city should comply with the objectives of (1) maximizing the profits from industries in the science park, (2) minimizing the damages incurred by the science park on its mother city, (3) decrease in consumption of natural resources, (4) reduction in environmental pollution, and (5) attention to relevant social problems.
The demand for water in Southern Taiwan has increased significantly in recent years because of industrial growth and increasing living standards. However, due to the financial reasons, only a limited scale of existing surface water facilities can be expanded in a river basin. Therefore, it often requires a suitable strategy to consider the fixed costs and operating costs for expansion. On the other hands, the conjunctive use of surface water and groundwater can enhance the reliability of water supplies by providing independent sources so that research on conjunctive use is important, especially with reference to fixed and operating costs. In light of above reason, resolving the tension between water deficit and economic profit, while ensuring the sustainable development of water resources is very urgent for government authorities. Accordingly, this investigation proposes a process of integrating the system dynamics and impact analysis for evaluating water strategy systematically and quantitatively, with reference to water shortage and economic profit as they pertain to the planning and management of regional water resources.
Simulation-based learning environments, often called management flight simulators or Microworlds, are excellent tools for giving people without modeling experience an intuitive understanding of complex systems. Learning environments let them experience the dynamics of complex systems without the hurdle of having to build models "from scratch". This workshop will deal with the design of learning environments, their user interfaces, underlying models, and workshop formats for experiencing with them. Special attention will be paid to methods of displaying information to help users understand causes of the behavior they encounter and thereby make better decisions and learn more quickly. The presenter will show a number of examples from his own work, but is also eager to make the workshop interactive and would like to hear about other people's experiences with learning environments and from people with models they are interested in turning into learning environments.
The U.S. health care system faces serious problems of high cost, limited access, unequal treatment, and inadequate health protection. Though these problems have persisted for decades and various reforms have been attempted, the overall impact of reform efforts has been only modest. This paper examines potential types of reform and the history of reform efforts. Causal-loop diagrams are presented which together comprise a theory to explain what created the set of problems that exist and why efforts at reform have largely failed. Different philosophical bases for reform and the need for an eclectic approach are discussed, and a sequential bootstrapping approach to comprehensive reform is outlined. The diagrams and discussion of this paper are intended as a starting point for further collaborative work on health care reform among system dynamics practitioners and health policy experts, leading to simulation modeling and further insights.