Скачать или смотреть Pareto Distribution and Price's Law

This is a visualisation of a trading game in which participants get a random outcome from a transaction between to parties. Over time the results follow that are often described as Price's law or the Pareto Distribution.

These are also often called the Matthew effect. Which comes from the following verse from the Bible:
For to every one who has will more be given, and he will have abundance; but from him who has not, even what he has will be taken away.
— Matthew 25:29, RSV.


Initially, all agents are given the same amount of money. After simulation starts, certain amounts of money Dm are repeatedly transferred from one randomly selected agent to another. If the selected agent does not have enough money to pay Dm , the transaction does not take place, and simulation continues with another pair of agents. The transfers of money are supposed to represent payments from one agent to another for certain products and services. However, we do not keep track of the goods offered in exchange for money and only keep track of money balances of all agents. The random character of money transfers is supposed to reflect the wide variety of products and connections in modern economy.

The histogram on the upper plot shows time evolution of the money distribution between the agents. As time goes on, the initial d-function distribution of money broadens. The vertical scale is adjusted with time, so that the histogram fits into the screen. Eventually, the money distribution stabilizes at the exponential shape, shown by the reference line in red, when the system reaches statistical equilibrium.

The bottom plot shows time evolution of the entropy of the money distribution. The entropy increases in time from the initial value 0 to the maximal value achieved when the system reaches statistical equilibrium

Credit to Justin Chen http://www2.physics.umd.edu/~yakovenk...