# Bayes' theorem

noun \ ˈbāz- \
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

## Origin and Etymology of bayes' theorem

Thomas Bayes †1761 English mathematician

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