How simple regulations can greatly reduce inequality

摘要

Many models of market dynamics make use of the idea of wealth exchanges amongeconomic agents. A simple analogy compares the wealth in a society with theenergy in a physical system, and the trade between agents to the energyexchange between molecules during collisions. However, while in physicalsystems the equipartition of energy is valid, in most exchange models foreconomic markets the system converges to a very unequal "condensed" state,where one or a few agents concentrate all the wealth of the society and thewide majority of agents shares zero or a very tiny fraction of the wealth. Herewe present an exchange model where the goal is not only to avoid condensationbut also to reduce the inequality; to carry out this objective the choice ofinteracting agents is not at random, but follows an extremal dynamics regulatedby the wealth of the agent. The wealth of the agent with the minimum capital ischanged at random and the difference between the ancient and the new wealth ofthis poorest agent is taken from other agents, so establishing a regulatorytool for wealth redistribution. We compare different redistribution processesand conclude that a drastic reduction of the inequality can be obtained withvery simple regulations.