StatPlay Topics The Law of Large Numbers

The Law of Large Numbers

See sample averages march toward the true mean as the trial count grows. A live animation that makes the Law of Large Numbers click — no formulas required.

I.02 / LAW OF LARGE NUMBERS

Law of Large Numbers

CLT showed that averages become normal. But does the sample mean actually converge to the true mean as n grows? That guarantee is the Law of Large Numbers. CLT describes the shape; LLN says the center won't run away.

10 heads in a row at the start of a coin-flip? Not that weird. But flip it 10,000 times and the head-ratio locks onto almost exactly 0.5.
That's the Law of Large Numbers — the more samples you draw, the more observed values get pulled toward the truth. This is why statistics counts as evidence, not a vague hunch.

Trials0
Current mean
Theoretical0.50
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