Size Effects in Agent-Based Macroeconomic Models: An Initial Investigation

We investigate the scale-free property of an agent-based macroeconomic model initially proposed by Wright (Physica A, 346:589–620, 2005), called the Social Architecture (SA) model. The SA model has been shown to be able to replicate a number of important features of a macroeconomy, such as patterns concerning economic growth, business cycles, industrial dynamics, and income distribution. We explore whether macroeconomic stylized features resulting from this model are robust when the number of agents populating the (model) economy varies. We simulate the model by systematically varying the agent population with 100, 500, 1,000, 2,000, 4,000, 8,000, and 10,000 agents. Our results indicate that the SA model does exhibit significant size effects for several important variables.