146,843 research outputs found

    Heterogeneous beliefs and and routes to complez dynamics in asset pricing models with price contingent contracts

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    This paper discusses dynamic evolutionary multi-agent systems, as introduced by Brock and Hommes (1997). In particular the heterogeneous agent dynamic asset pricing model of Brock and Hommes (1998) is extended by introducing derivative securities by means of price contingent contracts. Numerical simulations suggest that in a boundedly rational heterogeneous evolutionary world futures markets may be destabilizing.

    The influence of evolutionary selection schemes on the iterated prisoner's dilemma

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    Many economic and social systems are essentially large multi-agent systems. By means of computational modeling, the complicated behavior of such systems can be investigated. Modeling a multi-agent system as an evolutionary agent system, several important choices have to be made for evolutionary operators. Especially, it is to be expected that evolutionary dynamics substantially depend on the selection scheme. We therefore investigate the influence of evolutionary selection mechanisms on a fundamental problem: the iterated prisoner's dilemma (IPD), an elegant model for the emergence of cooperation in a multi-agent system. We observe various types of behavior, cooperation level, and stability, depending on the selection mechanism and the selection intensity. Hence, our results are important for (1) The proper choice and application of election schemes when modeling real economic situations and (2) assessing the validity of the conclusions drawn from computer experiments with these models. We also conclude that the role of selection in the evolution of multi-agent systems should be investigated further, for instance using more detailed and complex agent interaction models

    Generation-free Agent-based Evolutionary Computing

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    AbstractMetaheuristics resulting from the hybridization of multi-agent systems with evolutionary computing are efficient in many optimization problems. Evolutionary multi-agent systems (EMAS) are more similar to biological evolution than classical evolutionary algorithms. However, technological limitations prevented the use of fully asynchronous agents in previous EMAS implementations. In this paper we present a new algorithm for agent-based evolutionary computations. The individuals are represented as fully autonomous and asynchronous agents. Evolutionary operations are performed continuously and no artificial generations need to be distinguished. Our results show that such asynchronous evolutionary operators and the resulting absence of explicit generations lead to significantly better results. An efficient implementation of this algorithm was possible through the use of Erlang technology, which natively supports lightweight processes and asynchronous communication

    Evoplex: A platform for agent-based modeling on networks

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    Agent-based modeling and network science have been used extensively to advance our understanding of emergent collective behavior in systems that are composed of a large number of simple interacting individuals or agents. With the increasing availability of high computational power in affordable personal computers, dedicated efforts to develop multi-threaded, scalable and easy-to-use software for agent-based simulations are needed more than ever. Evoplex meets this need by providing a fast, robust and extensible platform for developing agent-based models and multi-agent systems on networks. Each agent is represented as a node and interacts with its neighbors, as defined by the network structure. Evoplex is ideal for modeling complex systems, for example in evolutionary game theory and computational social science. In Evoplex, the models are not coupled to the execution parameters or the visualization tools, and there is a user-friendly graphical interface which makes it easy for all users, ranging from newcomers to experienced, to create, analyze, replicate and reproduce the experiments.Comment: 6 pages, 5 figures; accepted for publication in SoftwareX [software available at https://evoplex.org

    Multi-agent evolutionary systems for the generation of complex virtual worlds

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    Modern films, games and virtual reality applications are dependent on convincing computer graphics. Highly complex models are a requirement for the successful delivery of many scenes and environments. While workflows such as rendering, compositing and animation have been streamlined to accommodate increasing demands, modelling complex models is still a laborious task. This paper introduces the computational benefits of an Interactive Genetic Algorithm (IGA) to computer graphics modelling while compensating the effects of user fatigue, a common issue with Interactive Evolutionary Computation. An intelligent agent is used in conjunction with an IGA that offers the potential to reduce the effects of user fatigue by learning from the choices made by the human designer and directing the search accordingly. This workflow accelerates the layout and distribution of basic elements to form complex models. It captures the designer's intent through interaction, and encourages playful discovery

    Evolutionary Computation of Multi-Robot/Agent Systems

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    A Multi-Agent Evolutionary algorIthm for Connector-Based Assembly Sequence Planning

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    AbstractSome Evolutionary algorithms for connector-based ASP have been researched. But those algorithms have lots of blind searching because individuals have little intelligence in making use of geometry and assembly process information of product assembly body. To improve individuals’ intelligence, A multi-agent evolutionary algorithm for connector-based ASP (MAEA-ASP) is presented which is integrated with the multi-agent systems. learning, competition and crossover -mutation are designed as the behaviors of agent which locate lattice-like structure environment. Experimental results show that MAEA-ASP can find an approximate solution faster compared with other evolutionary algorithms

    Strategy Competition Dynamics of Multi-Agent Systems in the Framework of Evolutionary Game Theory

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    There is the recent boom in investigating the control of evolutionary games in multi-agent systems, where personal interests and collective interests often conflict. Using evolutionary game theory to study the behaviors of multi-agent systems yields an interdisciplinary topic which has received an increasing amount of attention. Findings in real-world multi-agent systems show that individuals have multiple choices, and this diversity shapes the emergence and transmission of strategy, disease, innovation, and opinion in various social populations. In this sense, the simplified theoretical models in previous studies need to be enriched, though the difficulty of theoretical analysis may increase correspondingly. Here, our objective is to theoretically establish a scenario of four strategies, including competition among the cooperatives, defection with probabilistic punishment, speculation insured by some policy, and loner. And the possible results of strategy evolution are analyzed in detail. Depending on the initial condition, the state converges either to a domination of cooperators, or to a rock-scissors-paper type heteroclinic cycle of three strategies
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