law of averages

American  

noun

1. a statistical principle formulated by Jakob Bernoulli to show a more or less predictable ratio between the number of random trials of an event and its occurrences.

2. Informal. the principle that, in the long run, probability as naively conceived will operate and influence any one occurrence.

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law of averages British  

noun

1. (popularly) the expectation that a possible event is bound to occur regularly with a frequency approximating to its probability, as in the (actually false) example Compare law of large numbers

   after five heads in a row the law of averages makes tails the better bet

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law of averages Idioms  

1. The idea that probability will influence all occurrences in the long term, that one will neither win nor lose all of the time. For example, If it rains every day this week, by the law of averages we're bound to get a sunny day soon. This colloquial term is a popular interpretation of a statistical principle, Bernoulli's theorem, formulated in the late 1600s.

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Example Sentences

Perhaps the law of averages means this was bound to happen at some point, but, this season, two players already knew each other from having a mutual friend.

From BBC

He has not finished a season with just one goal since 2020-21, so the law of averages means he is due.

From BBC

I went with the law of averages when I picked a Newcastle home victory last week, so hopefully the same method will work again with Chelsea this time.

From BBC

“But over time, the law of averages plays out. You get what you deserve. The hockey gods know that.”

From Seattle Times

Still, the law of averages would suggest that, after jumping from 60 points one year to 100 to the next without a ton of significant additions, Seattle might drop off.

From Seattle Times