Bayes' theorem

[ beyz, bey-ziz ]

/ beɪz, ˈbeɪ zɪz /

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noun Statistics.

a theorem describing how the conditional probability of each of a set of possible causes, given an observed outcome, can be computed from knowledge of the probability of each cause and of the conditional probability of the outcome, given each cause.

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Origin of Bayes' theorem

see origin at Bayesian

Words nearby Bayes' theorem

bayberry, Bay City, Bayelsa, Bayern, Bayesian, Bayes' theorem, Bayeux, Bayeux tapestry, Bayezid II, bay-head bar, bay ice

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use Bayes' theorem in a sentence

The two wacky candidates combined for just over 5% of the vote with Brown pulling 3.3% and Bayes at 1.8%.
Who Voted For Idaho's Weirdo Candidates For Governor?|Ben Jacobs|May 21, 2014|DAILY BEAST
Obviously, these weren't the results that either Brown or Bayes were hoping for.
Who Voted For Idaho's Weirdo Candidates For Governor?|Ben Jacobs|May 21, 2014|DAILY BEAST
Two fringe candidates, Walt Bayes and Harley Brown were included and their participation made the debate go viral on the Internet.
Idaho’s Freakshow Debate|Ben Jacobs|May 16, 2014|DAILY BEAST
Bayes read Bible verses on stage and linked the 1986 nuclear disaster at Chernobyl to the Book of Revelations.
Idaho’s Freakshow Debate|Ben Jacobs|May 16, 2014|DAILY BEAST

Infinite Monkey Theorem has also landed praise in national publications including Wine Spectator as recently as last year.
Taste Off: Super Bowl State Wines From Colorado and Washington|Jordan Salcito|February 1, 2014|DAILY BEAST
This, however, is not a question of the method of the social science, but a theorem of the science itself.
A System of Logic: Ratiocinative and Inductive|John Stuart Mill
This was M. Comte's opinion; but it is by no means implied in his fundamental theorem.
A System of Logic: Ratiocinative and Inductive|John Stuart Mill
A modern historian aptly remarks that the medicine of the present "embraces nothing but a theorem of investigation by the senses."
An Epitome of the History of Medicine|Roswell Park
But as it seems not yet to have been stated clearly enough, I will here try to put my entire theorem into an unmistakable form.
The Stones of Venice, Volume III (of 3)|John Ruskin
But in the proof of this great theorem two influences were neglected, either of which is fatal to its validity.
A Text-Book of Astronomy|George C. Comstock

British Dictionary definitions for Bayes' theorem

Bayes' theorem

/ (beɪz) /

noun

statistics the fundamental result which expresses the conditional probability P (E/A) of an event E given an event A as P (A/E). P (E) /P (A); more generally, where E n is one of a set of values E i which partition the sample space, P (E n /A) = P (A/E n) P (E n) / Σ P (A/E i) P (E i). This enables prior estimates of probability to be continually revised in the light of observations

Word Origin for Bayes' theorem

C20: named after Thomas Bayes (1702–61), English mathematician and Presbyterian minister

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012