Not a natural occurrence of disparity.

Forty people have ten coins each. A randomly selected person X receives one coin from a randomly selected person Y. The figure shows the graph after one coin is passed. As this coin transfer is repeated, disparity expands, and in this experiment, there are people who have zero coins after the 489th coin transfer. For clarity, sorting by the number of coins you have is as follows.

Some people find these results “surprising. I was surprised that “some people find this result surprising. How surprising is it? “0.1 is so small, it’s almost 0, but if you add it 1000 times, you get 100! That’s so unexpected, isn’t it? It’s so unexpected.

The first “everyone has 10 coins” situation is indeed “zero disparity”. But after one step, “someone is down one card and someone is up one card” is already not zero disparity. Specifically, the decentralization of random variable, “1 out of 40 is +1 and 1 is -1” is 0.05. When independent random variables are added together, the variance is also added. If the coins are passed and received 489 times, the variance would be 0.05 + 0.05 + … and would be added 489 times. The variance of the distribution at the time of the final bankruptcy was 24.6. Dividing this by 489 gives 0.0503. So each delivery is increasing by 0.05 in order. It’s just like the theory says.

So, “0.05 is so small, it’s almost zero, yet if you add that 489 times, you get 24.6!” The feeling of being told. That’s a given.

- [[Non-intuitive behavior]]

• Code for this experiment:

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