Glossary

Law of truly large numbers

With enough people, days and chances, even very unlikely coincidences are certain to happen to someone, somewhere, regularly.

In plain English

A one-in-a-million event per person per day happens to more than 300 people in the US every day. Coincidences feel meaningful because we see the hit and not the millions of chances that produced it. The useful question is not 'how unlikely is this?' but 'how many chances were there for something like this to happen?'.

Uncle Gary explains

Aunt Linda sees 11:11 several times a week. She also checks the time about 50 times a day, which gives the clock plenty of chances to look meaningful.

Why it matters for your money

Out of thousands of traders and funds, some will have astonishing records by luck alone. The record is real; the meaning may not be.

Where we tested it

Related terms

All glossary terms. Educational content, not financial advice.