  We present a detailed numerical analysis of the modified version of a
conservative self-organized extremal model introduced by Pianegonda et. al. for
the distribution of wealth of the people in a society. Here the trading process
has been modified by the stochastic bipartite trading rule. More specifically
in a trade one of the agents is necessarily the one with the globally minimal
value of wealth, the other one being selected randomly from the neighbors of
the first agent. The pair of agents then randomly re-shuffle their entire
amount of wealth without saving. This model has most of the characteristics
similar to the self-organized critical Bak-Sneppen model of evolutionary
dynamics. Numerical estimates of a number of critical exponents indicate this
model is likely to belong to a new universality class different from the well
known models in the literature. In addition the persistence time, which is the
time interval between two successive updates of wealth of an agent has been
observed to have a non-trivial power law distribution. An opposite version of
the model has also been studied where the agent with maximal wealth is selected
instead of the one with minimal wealth, which however, exhibits similar
behavior as the Minimal Wealth model.
