Suchergebnisse

Intro -- Foreword -- Contents -- Contributors -- Introduction -- 1 Getting Started: The Aggregation Conundrums and Basic Toolkits of Agent Based Modeling -- 1.1 Understanding Heterogeneity and Interaction in Economic Models -- 1.1.1 Aggregate Models with Boundlessly Rational Agents -- 1.1.2 The Aggregation Problem -- 1.1.3 The Standard Approach and the Aggregation Problem -- 1.1.4 A Didactic Example Comparing ABM with the Standard Approach -- 1.1.5 Behavioral Rules and Aggregation in ABM -- 1.1.6 Aggregation in ABM with Network Effects -- 1.2 Basic Macroeconomic Agent Based Tools -- 1.2.1 Macroeconomic Building Blocks -- 1.2.2 Expectations -- 1.2.3 Production and Credit -- 1.2.4 Innovation -- 1.2.5 Consumption -- 1.2.6 Government and Central Bank -- 1.2.7 Exit and Enter -- 1.3 Basic Financial Agent Based Tools -- 1.3.1 Financial Building Blocks -- 1.3.2 Microfoundations and Behavioural Rules -- 1.3.3 Market Microstructure -- 2 A Simple Model of Business Fluctuations with Heterogeneous Interacting Agents and Credit Networks -- 2.1 Getting Started: Implementing a Toy Model -- 2.1.1 Model Theoretical Setup -- 2.1.2 Implementing the Model Using R -- 2.1.3 Simulating the Model -- 2.1.4 Some Variations -- 2.1.5 Multiple Simulations -- 2.1.6 A LargeŽ Computational Experiment -- 2.1.7 Sensitivity Analysis -- 2.1.8 A Policy Experiment -- 2.2 Going Further: Heterogeneous Agents and Credit Networks -- 2.2.1 Model Setup -- 2.2.2 Implementing the Model with R -- 2.2.3 Implementing the Model in R -- 2.2.4 Sensitivity -- 2.2.5 Policy Experiment -- 2.2.6 Network Analysis -- 2.2.7 Network Statistics -- 2.3 A Calibration Experiment -- 2.4 Exercise -- 3 Modeling Financial Markets in an Agent-Based Framework -- 3.1 Introduction -- 3.2 The Model -- 3.2.1 The Market Microstructure -- 3.2.2 The Communication Network.

Agent-based modeling/simulation is an emerging field that uses bottom-up and experimental analysis in the social sciences. This book includes selected research from that presented at the Third International Workshop on Agent-Based Approaches in Economic and Social Complex Systems 2004, held in May 2004 in Kyoto, Japan

We analyze the evolution and extent of income tax evasion under alternative governmental policies in an agent-based model with heterogeneous agents. A novel aspect of our modeling is the use of an exponential utility function, which allows us to assume rather realistic audit probabilities and to yield more realistic results with respect to the extent of tax evasion. Further, the introduction of lapse of time effects constitutes another novel aspect of our model. Among other things, the model allows for assessing the impact of alternative policies on tax evasion. Subject to the model features, we find that ethical norms and lapse of time effects reduce the extent of tax evasion particularly strong.

In this paper, a multi-agent based simulation platform is introduced that focuses on legitimate and illegitimate aspects of maritime traffic, mainly on intercontinental transport through piracy afflicted areas. The extensible architecture presented here comprises several modules controlling the simulation and the life-cycle of the agents, analyzing the simulation output and visualizing the entire simulated domain. The simulation control module is initialized by various configuration scenarios to simulate various real-world situations, such as a pirate ambush, coordinated transit through a transport corridor, or coastal fishing and local traffic. The environmental model provides a rich set of inputs for agents that use the geo-spatial data and the vessel operational characteristics for their reasoning. The agent behavior model based on finite state machines together with planning algorithms allows complex expression of agent behavior, so the resulting simulation output can serve as a substitution for real world data from the maritime domain.

Although Agent Based Models (hereafter ABM) are now regularly reported in sociology journals, explaining the approach, describing models and reporting results leaves little opportunity to examine wider implications of ABM for sociological practice. This article uses an established ABM (the Schelling model) for this. The first part argues that ABM integrates qualitative and quantitative data distinctively, provides novel tools for understanding social causes and offers a significantly different perspective on theory building. The second part shows how the emerging ABM methodology is compatible with existing sociological practice while undermining several criticisms of ABM perceived to limit its sociological relevance.

An agent-based computer simulation demonstrates that results from Downs, Duverger, Riker, and Sundquist can be seen as emergent consequences of five simple rules about iteratively forming coalitions and adjusting policy platforms. The model creates distributions of agents who form coalitions within a political body. By modifying and omitting the basic rules, I compare results from plurality and majority-seeking actors and from policy-seeking, office-seeking, and mixed-strategy coalitions. A set of simple rules implemented by agents with extremely bounded knowledge are sufficient to drive the classic median voter, two-party system, minimum winning coalitions, and party realignment results in a single framework.