Bayes' theorem


variants or less commonly Bayes theorem or less commonly Bayes's theorem
: a theorem about conditional probabilities: the probability that an event A occurs given that another event B has already occurred is equal to the probability that the event B occurs given that A has already occurred multiplied by the probability of occurrence of event A and divided by the probability of occurrence of event B

Word History


Thomas Bayes †1761 English mathematician

First Known Use

1830, in the meaning defined above

Time Traveler
The first known use of Bayes' theorem was in 1830

Dictionary Entries Near Bayes' theorem

Cite this Entry

“Bayes' theorem.” Dictionary, Merriam-Webster, Accessed 15 Jul. 2024.

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