Before revision:  Evolution is driven by multiplicative stochastic fluctuations governed by the law of proportionate growth as well as by direct interactions between individuals and interactions between the private and public sectors. We concentrate on the effect of accumulated advantage and study the role of taxation and redistribution in the process of reducing wealth inequality.
After revision:  Evolution is driven by multiplicative stochastic fluctuations governed by the law of proportionate growth as well as by direct interactions between individuals and interactions between agents. We are mainly interested in interactions increasing wealth inequality that is in a local implementation of the accumulated advantage principle. Such interactions destabilise the system. They are confronted in the model with a global regulatory mechanism which reduces wealth inequality.