Bayes' theorem

\ ˈbāz- How to pronounce Bayes' theorem (audio) \
variants: or less commonly Bayes theorem or less commonly Bayes's theorem

Definition of Bayes' 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

First Known Use of Bayes' theorem

1830, in the meaning defined above

History and Etymology for Bayes' theorem

Thomas Bayes †1761 English mathematician

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The first known use of Bayes' theorem was in 1830

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Cite this Entry

“Bayes' theorem.” Dictionary, Merriam-Webster, Accessed 14 Aug. 2020.

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