Exploring Wealth Distribution Through Sugarscape Jordan Albright
Purpose Analyze the wealth distribution of agents in Sugarscape over time Compare calculations with other studies Assess validity of project in scope of social science
Similar Studies An Agent-Based Model of Wealth Distribution Impullitti and Rebmann, 2002 Studied sugarscape wealth distribution in context of classical and neo-classical economics Found it difficult to bridge model and reality in agent based modeling
Similar Studies (cont.) Aligning Simulation Models: A Case Study and Results Axtell, Axelrod, Epstein, Cohen, 1996 Attempted to synthesize results from Sugarscape and Axelrod model Difficult to streamline results of models when given same initial conditions
Sugarscape Movement –Vision Reproduction Death Sugar regrowth
Wealth Distribution Analysis Lorenz Curve –Proportion of distribution –Line of perfect equality –Basis for many other functions
Wealth Distribution Analysis Gini coefficient –Measure of inequality –Ratio ranging from 0 to 1 –Typical range of developed countries:.3 to.4
User Controls User can specify: –Initial population –Birth energy –Max. metabolism and vision –Inheritance on or off –Display vision of agents
Results Comparison of results with Impullitti: –Gini coefficient in project Without inheritance:.35 to.4 With inheritance:.4 to.5 –Gini coefficient in Impullitti:.3 to.33 Different rules for agents Different initial conditions
Results (cont.) Non-inherited Small fluctuations in GC, vision, metabolism
Results (cont.) Inherited Metabolism approaches lower limit Vision increases but does not reach maximum
Results (cont.) Based on visual representation, bottlenecking Regions of unequal wealth distribution