Bayesian

American  

[bey-zee-uhn, -zhuhn] / ˈbeɪ zi ən, -ʒən /

adjective

Statistics.

1. of or relating to statistical methods that regard parameters of a population as random variables having known probability distributions.

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Bayesian British  

/ ˈbeɪzɪən /

adjective

1. (of a theory) presupposing known a priori probabilities which may be subjectively assessed and which can be revised in the light of experience in accordance with Bayes' theorem. A hypothesis is thus confirmed by an experimental observation which is likely given the hypothesis and unlikely without it Compare maximum likelihood

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Etymology

Origin of Bayesian

1960–65; Thomas Bayes (1702–61), English mathematician + -ian

Example Sentences

For some, the Bayesian framework is essentially a working definition of rationality or common sense: As one learns more, one’s views change—whether about the weather or the deadliness of a disease like Covid-19.

From The Wall Street Journal • Mar. 29, 2026

To determine how this species fits into the evolutionary history of humans, the researchers used a Bayesian "tip-dating" method.

From Science Daily • Mar. 27, 2026

We recently endorsed greater use of Bayesian statistics in small studies and for identifying optimal dosing for children.

From The Wall Street Journal • Feb. 23, 2026

Even so, the researchers succeeded in updating the controller's internal Bayesian model after every single qubit measurement.

From Science Daily • Feb. 20, 2026

I explained it all to him, the Bayesian stuff and my fear that we couldn't go on using Xnet the way we had been without getting nabbed.

From Little Brother by Doctorow, Cory