  In this paper, we investigate the economic mobility in some money transfer
models which have been applied into the research on wealth distribution. We
demonstrate the mobility by recording the time series of agents' ranks and
observing their volatility. We also compare the mobility quantitatively by
employing an index, "the per capita aggregate change in log-income", raised by
economists. Like the shape of distribution, the character of mobility is also
decided by the trading rule in these transfer models. It is worth noting that
even though different models have the same type of distribution, their mobility
characters may be quite different.
