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Introduction to Agent-Based Modeling. Teaching Contemporary Mathematics Conference January 25, 2013 Christine Belledin NC School of Science and Mathematics. Models where individuals in the environment are unique and autonomous Individuals vary in certain characteristics such as Location - PowerPoint PPT Presentation
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Teaching Contemporary Mathematics ConferenceJanuary 25, 2013
Christine BelledinNC School of Science and Mathematics
Introduction toAgent-Based Modeling
Models where individuals in the environment are unique and autonomous
Individuals vary in certain characteristics such as Location Ability or skill level Resource reserves
Individuals interact with each other and their environment Agents have only local knowledge and interactions Each agent pursues its own objectives
Agents use adaptive behavior – they adjust their behavior based on their current state, their neighboring agents, or their environment
What is Agent-Based Modeling?
ABM’s can be used to study system dynamics that arise from the way that individual agents interact with each other and their environments
ABM’s are across-level modelsExamples of questions ABM’s have been used to investigate
How can we manage tropical forests in a sustainable way? How do shorebird populations respond to loss of the mudflats they feed in,
and how can this be addressed in a cost-effective way? What causes the complex and seemingly unpredictable dynamics of a stock
market? How should electricity grids be developed in developing countries?
Uses of Agent-Based Models
Based on work by Nobel laureate Thomas SchellingExplores relationship between segregation patterns and
tolerance of individuals for unlike neighbors
Example 1: Segregation Model
Example 2: Spread of a Fire
First consider the original model where birds change their heading based on multiple neighbors.
Example 3: Flocking Model
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Example 3: Flocking Model
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Example 3: Flocking Model
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Shows distribution of wealth over time as measured graphically by a class histogram and numerically by the Gini Index
Example 4: Distribution of Wealth
The Gini IndexPerfect equity: Gini Index = 0
Perfect inequity: Gini index = 1
Example 5: Spread of Disease
