Suchergebnisse

We use an agent-based model to investigate the interdependent dynamics between individual agency and emergent socioeconomic structure, leading to institutional change in a generic way. Our model simulates the emergence and exit of institutional units, understood as generic governed social structures. We show how endogenized trust and exogenously given leader authority influences institutional change, i.e., diversity in institutional life-cycles. It turns out that these governed institutions (de)structure in cyclical patterns dependent on the overall evolution of trust in the artificial society, while at the same time, influencing this evolution by supporting social learning. Simulation results indicate three scenarios of institutional life-cycles. Institutions may, (1) build up very fast and freeze the artificial society in a stable but fearful pattern (ordered system); (2) exist only for a short time, leading to a very trusty society (highly fluctuating system); and (3) structure in cyclical patterns over time and support social learning due to cumulative causation of societal trust (complex system).

We use an agent-based model to investigate the interdependent dynamics between individual agency and emergent socioeconomic structure, leading to institutional change in a generic way. Our model simulates the emergence and exit of institutional units, understood as generic governed social structures. We show how endogenized trust and exogenously given leader authority influences institutional change, i.e., diversity in institutional life-cycles. It turns out that these governed institutions (de)structure in cyclical patterns dependent on the overall evolution of trust in the artificial society, while at the same time, influencing this evolution by supporting social learning. Simulation results indicate three scenarios of institutional life-cycles. Institutions may, (1) build up very fast and freeze the artificial society in a stable but fearful pattern (ordered system) ; (2) exist only for a short time, leading to a very trusty society (highly fluctuating system) ; and (3) structure in cyclical patterns over time and support social learning due to cumulative causation of societal trust (complex system).

We use an agent-based model to investigate the interdependent dynamics between individual agency and emergent socioeconomic structure, leading to institutional change in a generic way. Our model simulates the emergence and exit of institutional units, understood as generic governed social structures. We show how endogenized trust and exogenously given leader authority influences institutional change, i.e., diversity in institutional life-cycles. It turns out that these governed institutions (de)structure in cyclical patterns dependent on the overall evolution of trust in the artificial society, while at the same time, influencing this evolution by supporting social learning. Simulation results indicate three scenarios of institutional life-cycles. Institutions may, (1) build up very fast and freeze the artificial society in a stable but fearful pattern (ordered system); (2) exist only for a short time, leading to a very trusty society (highly fluctuating system); and (3) structure in cyclical patterns over time and support social learning due to cumulative causation of societal trust (complex system).

After reviewing the main empirical and theoretical findings about the evolution of inequality and its impact on macroeconomic dynamics, this thesis expands the analysis performed with an agent-based model by Napoletano, Roventini and Gaffard (2016). In the model, which is characterized by heterogeneous households with credit constraints, an inequality shock is introduced. This generates a fall in aggregate demand and income. Scenarios with different degrees of inequality are compared, and what emerges is that higher inequality is associated with more severe recessions. Moreover, a redistributive fiscal policy, in the form of a subsidy, is introduced after the crisis. This policy significantly dampens the fall in aggregate output implied by the inequality shock and is more effective than direct government expenditure in stimulating the economy.

Sovereign default contagion in Eurozone has been under attention since the first problems in Greece at the end of 2009. Despite the improvements in the situation, in particular after several European Central Bank non- conventional monetary policy measures, the roots of the problem and policy prescriptions are still fiercely debated today. Using an agent-based model adapted from Tirole (2015), we simulate sovereign default contagion in a world where countries have random incomes, heterogeneous borrowing behaviors and risk aversion levels and where governments have the possibility to enter in ex-ante agreements to protect against default. We conclude that default contagion can be a very fast and 'destructive' process, higher spending countries tend to have lower disposable incomes and higher risk aversion levels are associated with lower default rates. ; info:eu-repo/semantics/publishedVersion

"I develop an agent-based computational economics (ACE) model with which I evaluate the aggregate impact of labor market policies. The findings are that governmentfinanced training measures increase the outflow rate from unemployment to employment. Although the overall effect is positive this effect is achieved by reducing the outflow rate for those who do not receive subsidies. Furthermore, the outflow rate would have been downward-biased had one supposed a matching function that is exogenous to policies." (author's abstract)

As societies face the challenge of securing an efficient and environmentally sound energy supply, researchers have strived to determine the future development of energy consumption, infrastructure and technology endowment. This book proposes a new agent-based approach to studying the development of urban energy systems. Decisions of private and commercial investors and operators are modeled using a bounded rational decision model which are parameterized by socio-economic data. The study goes on to analyze the impact of firms??? competition on technology diffusion and calculate diffusion curves.

from Scythe : Proceedings and Bulletin of the International Data Farming Community, Issue 1 Workshop 13 ; Agent-based models have recently gained in popularity for modelling military operations. They purposefully leave out detailed physical attributes of the military entities concerned if this is not expected to have any bearing on the study at hand. This allows scenarios to be run relatively fast, over many excursions in order to discover unique situations or tactics where friendly forces can achieve dominance over an enemy. Another key feature of agent-based models is that, although the one-to-one interaction between various agents and their environment may be quite simple, the combined effect of many agents interacting can lead to complicated group dynamics and emergent behaviour. In this regard, agent-based models have the potential to represent the more chaotic and intangible aspects of military conflicts.

Agent-based models (ABMs) are an increasingly popular tool in the social sciences. This trend seems likely to continue, so that they will become widely used in geography and in urban and regional planning. We present an overview of examples of these models in the life sciences, economics, planning, sociology, and archaeology. We conclude that ABMs strongly tend towards an individualist view of the social world. This point is reinforced by closer consideration of particular examples. This discussion pays attention to the inadequacy of an individualist model of society with reference to debates in social theory. We argue that because models are closed representations of an open world it is important that institutions and other social structures be explicitly included, or that their omission be explained. A tentative explanation for the bias of ABMs is offered, based on an examination of early research in artificial intelligence and distributed artificial intelligence from which disciplines the approach is derived. Some implications of these findings are discussed. We indicate some useful research directions which are beginning to tackle the individualism issue directly. We further note that the underlying assumptions of ABMs are often hidden in the implementation details. We conclude that such models must be subject to critical examination of their assumptions, and that model builders should engage with social theory if the approach is to realise its full potential.

Like many developing countries, Nigeria, is faced with a number of tradeoffs that pit rapid economic development against environmental preservation. Environmentally sustainable,"green" economic development is slower, more costly, and more difficult than unrestricted, unregulated economic growth. In this paper we develop an agent-based computational model of agents (who can be individuals or organizations) in a population who make successive choices that have economic and environmental impacts. Simulations based on the model suggest that widespread public awareness of environmental issues is insufficient to prevent the tendency towards sacrificing the environment for the sake of growth. Even if people have an understanding of negative impacts and always choose to act in their own self-interest, they may still act collectively in such a way as to bring down the quality of life for the entire society. We conclude that besides raising public awareness, economic intervention by the government (in the form of incentives or penalties) may be the only way to achieve an optimal balance between economic and environmental factors.

Many agent-based models (ABMs) try to explain large-scale phenomena by reducing them to behaviors at lower scales. At these scales in social systems are functional groups such as households, religious congregations, coops and local governments. The intra-group dynamics of functional groups often generate inefficient or unexpected behavior that cannot be predicted by modeling groups as basic units. We introduce a framework for modeling intra-group decision-making and its interaction with social norms, using the household as our focus. We select phenomena related to women's empowerment in agriculture as examples influenced by both intra-household dynamics and gender norms. Our framework proves more capable of replicating these phenomena than two common types of ABMs. We conclude that it is not enough to build multi-scale models; explaining social behaviors entails modeling intra-scale dynamics.

I develop an agent-based computational economics (ACE) model with which I evaluate the aggregate impact of labor market policies. The findings are that governmentfinanced training measures increase the outflow rate from unemployment to employment. Although the overall effect is positive this effect is achieved by reducing the outflow rate for those who do not receive subsidies. Furthermore, the outflow rate would have been downward-biased had one supposed a matching function that is exogenous to policies. ; Im Folgenden wird ein agenten-basiertes Modell entwickelt, mit dem die aggregierten Wirkungen von Arbeitsmarktpolitiken evaluiert werde können. Ein Resultat ist, dass die Subvention von Trainingsmaßnahmen die Übergangsrate von Arbeitslosigkeit in Beschäftigung erhöht. Obwohl der Gesamteffekt positiv ist, reduziert sich die Übergangsrate für all jene Arbeitslose, deren Ausgaben nicht subventioniert werden. Der Verdrängungseffekt ist bei einer plausiblen Parametrisierung des Modells in seiner Höhe ökonomisch relevant. Ferner wäre die Messung der Übergangsrate aus Arbeitslosigkeit in Beschäftigung nach unten verzerrt gewesen, hätte man in der Wirkungsanalyse angenommen, dass die Matching-Funktion exogen zu den Arbeitsmarktpolitiken ist.

It is a common phenomenon that at any gathering, people cluster into small and multiple groups to: chat, exchange ideas, establish relations, and explore collaborative opportunities either within their field of work or even in newer frontiers. Certain relationships remain strong and may eventually lead to fruitful collaborations while others may be short lived. Depiction and/or modelling of such an emergent social networking behaviours are inherently complex. With this motivation, in the context of an academic conference, this research focuses on the development of ' Networking of Scholars at an Academic Conference ( NASC) Model' using Agent Based Modelling and Simulation (ABMS) technique. The paper describes the model and its implementation in NetLogo. NetLogo is powerful programming environment that facilitates the generation of scenarios and thus helps visualisation of emergent network of relationships among scholars.