Gambler's fallacy facts for kids

This picture shows a coin being flipped. Over many flips, the number of red and blue results gets closer to being equal, like 50-50.

The Gambler's Fallacy is a common mistake people make about statistics and chance. It's also called the Monte Carlo Fallacy. This idea makes people think that if something has happened a lot in the past, it's less likely to happen again soon. Or, if it hasn't happened much, it's "due" to happen more often.

But here's the truth: for truly random events, like flipping a coin, what happened before doesn't change what will happen next. Each flip is a fresh start!

What is the Gambler's Fallacy?

This fallacy is a misunderstanding of probability. Imagine you flip a coin. The chance of getting heads is 50%, and the chance of getting tails is 50%. If you flip heads five times in a row, the Gambler's Fallacy makes you think that the next flip is more likely to be tails. You might feel like tails is "due."

However, the coin doesn't "remember" what happened before. The chance of getting tails on the next flip is still 50%. Each flip is an independent event. This means its outcome doesn't depend on previous outcomes.

Gambler's Fallacy and Births

People have believed in the Gambler's Fallacy for a long time. For example, in 1796, a scientist named Pierre-Simon Laplace wrote about how people thought about having children. Some fathers worried that if many boys were born in their town, they would be more likely to have a daughter. They thought the number of boys and girls born should always be equal.

Even today, some parents might think that after having several children of the same sex, they are "due" to have a child of the opposite sex. For example, if a family has three boys, they might believe their next child is more likely to be a girl. But just like a coin flip, the chance of having a boy or a girl is still about 50% for each new baby, no matter how many children of one sex they already have.

Images for kids

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  Over time, the number of red and blue coin tosses gets closer to being equal, but the actual difference between them doesn't always go down to zero.

See also

In Spanish: Falacia del apostador para niños