Start with 100 identical agents, each holding 100 units of wealth.
At each step:
- Pick two random agents.
- Calculate 10% of the poorer agent’s wealth.
- Flip a coin — one agent gives that amount to the other.
Repeat this 100,000 times.
Despite fair rules, inequality emerges: a few agents get rich, many get poor.
The plot shows wealth distribution at the start ( red) and end ( blue) of the simulation.
Dragulescu, A., & Yakovenko, V. M. (2000). Statistical mechanics of money. Eur. Phys. J. B, 17(4), 723–729. https://doi.org/10.1007/s100510070114
Start with 100 identical agents, each holding 100 units of wealth.
At each step:
- Pick one agent at random, weighted by how much wealth they already have.
- Give them 1 additional unit of wealth.
Repeat this 100,000 times.
Early luck snowballs: the rich get richer, the poor fall behind.
The plot shows wealth distribution at the start ( red) and end ( blue) of the simulation.
Merton, R. K. (1968). The Matthew Effect in Science. Science, 159(3810), 56–63.
