Wealth Distributions in Asset Exchange Models

How do individuals accumulate wealth as they interact economically? We outline the consequences of a simple microscopic model in which repeated pairwise exchanges of assets between individuals build the wealth distribution of a population. This distribution is determined for generic exchange rules — transactions that involve a fixed amount or a fixed fraction of individual wealth, as well as random or greedy exchanges. In greedy multiplicative exchange, a continuously evolving power law wealth distribution arises, a feature that qualitatively mimics empirical observations.