Abstract
An agent-based model of artificial economic system including consumer, firm, bank and government has been developed and the influences of public policies on GDP and related emergent behavior of macroeconomic phenomena have been analyzed. It was revealed that power law distributions emerge during simulation in some factors such as assets of agents and GDP increases with an increase in the ratio of efficient expenditure policy such as market purchasing. Average price increases or decreases when GDP increases or decreases, and the influence of tax rate on GDP depends on the way of public spending. Most of these results are found to be quite consistent with real data, if it is assumed that public spending includes more than 10% of inefficient factors.
