The main aims of this study is underline that System Dynamics approach allows the building of a general framework in which psychological, economic, social, legal and organizational variables converge to describe the retirement behaviour and its main unintended consequences. Its emphasized that organizational commitment and psychological contract breach play a considerable role in the dynamics of retirement behaviour. In the first part of this paper, an analysis of main contributions in the retirement and early retirement fields is outlined. Further, the social, economical and legal approach to retirement behaviour is also briefly remarked. In the second part, retirement phenomenon, dynamics of the key-variables, problem issues, feedback analysis of adopted public policies, unintended consequences of public policies and policy design to remove these consequences are discussed. Results confirm that system archetypes are fundamental in the understanding the complex system that countersign retirement behaviour.
The Insider Threat Study, conducted by the U.S. Secret Service and Carnegie Mellon Universitys Software Engineering Institute CERT Program, analyzed insider cyber crimes across U.S. critical infrastructure sectors. The study indicates that management decisions related to organizational and employee performance sometimes yield unintended consequences magnifying risk of insider attack. Lack of tools for understanding insider threat, analyzing risk mitigation alternatives, and communicating results exacerbates the problem. The goal of Carnegie Mellon Universitys CyLab-funded MERIT (Management and Education of the Risk of Insider Threat) project is to develop such tools. MERIT uses system dynamics to model and analyze insider threats and produce interactive learning environments. These tools can be used by policy makers, security officers, information technology, human resources, and management to understand the problem and assess risk from insiders based on simulations of policies, cultural, technical, and procedural factors. This paper describes the MERIT insider threat model and simulation results.
This paper develops a model that explains how and under what circumstances firms can realize expansion economies. In order to exploit economies of expansion while augmenting benefits, manufacturing firms tend to extend their economic activities to different locations, regions and countries. The level to which firms spread out in a region depends on the local demand. When such local demand is completely satisfied by the firm, it may decide to star business activities in other region. Firms expansion process is limited by the size of the market whose boundary is the world demand. The growth of the firm through expansion economies depends on the scale of the different elements that form the basic business unit. In this paper it is also shown that expansion economies is a special case of increasing returns that cause neither dominant firm nor dominant technology.
Zero-to-Landfill is a strategy that is gaining increasing attention throughout the world, driven by legal mandates and consumer demand. A product take-back process is required to ensure products that reach the end of their useful lives are reclaimed for reuse, remanufacturing, or recycling. We previously reported on a model of the material flows that exist within a take-back process. The results of dynamic simulations of a hypothesized take-back strategy enabled us to identify several policies and opportunities that, if executed, would minimize the material sent to landfills over the life cycle of a product. We proposed several extensions and modifications of our model that would improve the results and behavior of the simulations. In this paper, we present an improved model of a reverse logistics system for a consumer product. The impacts of closed-loop policies on material reclamation, product adoption rate, and product costs are investigated. We illustrate the relationships between the collection, processing, and reuse rates, and how the amount of material reused influences product costs, product sales, and, ultimately, corporate revenues and profits. A Zero-to-Landfill strategy is shown to have a significant potential to improve the triple bottom line people, planet, and profit of companies that adopt it.
For the benefit of a sustainable global development of energy consumption and its climatic impact the per-capita energy consumption in industrialised countries such as Switzerland shall be reduced, with the vision of not exceeding the actual global average of 2000 Watts. Reaching this goal affects all sectors, particularly the building and the transportation sector, as a main originator of CO2-emissions in Switzerland. In this sector, the most important effect is achieved by not only reducing consumption but also advancing alternative drive train technologies. The market penetration of these new technologies is to be modeled in order to learn more about the fundamental processes and derive strategies contributing to their successful introduction. An existing system dynamics model for the market penetration of passenger cars with new drive train technologies, focusing on natural gas vehicles (NGVs) as a first alternative to conventional gasoline and diesel cars, forms the basis for further work and is shortly described. Possible extensions, mainly in the customer sector, are discussed, as well as the introduction of different model layers for additional drive train technologies competing with each other. Finally a game theoretical approach to simulate the exogenous stakeholders shall link them closer to the system dynamics model.
This is a hands-on introductory workshop. The attendees will be able to build models of both System Dynamics and Agent Based kinds using AnyLogic, and, if time allows, a hybrid model. The goal of the workshop will be not just to demonstrate the software but also to discuss when agent based modeling makes sense and what needs to be done to make it practically useful. You can download and install AnyLogic prior to the workshop, or we can supply you with the CDs and demo keys in Nijmegen.
This research uses a case study to explore leverage in reducing "disconnects" in baselines across multiple organizations in a large space system development program. Disconnects, latent differences in understanding that can negatively affect the program should they remain undetected or unresolved, can jeopardize program targets for cost, schedule, performance, and quality. In addition to case-study analysis, we constructed and analyzed a formal dynamic model of communication effectiveness across four organizations that rely on each other for requirements and deliverables. Findings to date refute common beliefs that disconnects result primarily from external stakeholders requirements changes and that speeding up organizational processes will reduce disconnects. Instead, analyses suggest that the greatest leverage in reducing disconnectsand therefore mitigating program riskslies in increasing expertise, improving communication clarity, and accelerating the pace of assessing impacts from changes in other organizations' understandings and actionsbut not accelerating the pace of acting on those assessments.
Increasing complexity and uncertainty of both business internal and external variables determines a growing need for prompt and accurate information. On this concern, in the last decade, there has been an increasing effort to provide public utilities with tools aimed to support decision makers in planning and control, by taking into account not only operational but also strategic issues. Among them, for instance, customer satisfaction, internal business process efficiency, business image, and bargaining power against other counterparts (e.g. the municipal administration). Quite often, however, such an effort has been oriented to generate a large volume of data, only focused on financial indicators and on a static view of the relevant system. This article shows how the use of Balanced Scorecards based on System Dynamics models can significantly improve the planning process in a strategic learning perspective. Empirical findings from a research project conducted in a municipal water company are analysed and discussed.
Based on a review of existing literature in management and economics of arts and culture and on an extensive case study the metropolitan museum district in Turin this papers objective is to show that museum growth is problematic in the long term through a system dynamics model. The classical loop investments, growth, profitability, investment encounters difficulties when dealing with public goods, characterized by high interconnections among museums and stakeholders within the same territory. The model simulation shows the structural characteristics of this sector that determines problems in term of survival; it can thus be understood as blending management and economic perspectives. Therefore, the search for sustainability should be addressed in controlling museum growth with a long time perspective and in supporting and developing new forms of cooperation among those organizations to decrease the cost of growth.
The Greater sage-grouse (Centrocercus urophasianus) occupies the sage brush habitats of Western North America. Large population declines in the last several decades have made it a candidate for possible listing under the Endangered Species Act. Listing was recently avoided in part because seventy local working groups are developing long-range management plans in conjunction with federal and local agencies. The Foster Creek Conservation District, a working group in Douglas County, Washington, saw the potential for system dynamics to synthesize known sage-grouse dynamics and local land use patterns to support development of their Habitat Conservation Plan and subsequent land management decisions. The resulting model is providing insights into the cropland and shrub steppe ecosystems of Douglas County and the management scenarios which may prevent the sage-grouse from an endangered status. The model is designed to facilitate and support land use management decisions through the collaborative exploration of model parameters and simulated scenarios.