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

To address this, the researchers used Bayesian spatio-phylogenetic analyses, which account for both shared ancestry and geographic influence.

From Science Daily • Apr. 5, 2026

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

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

In a groundbreaking step, researchers at the University of Tokyo applied a type of artificial intelligence known as a Bayesian neural network to study gut bacteria.

From Science Daily • Nov. 10, 2025

It's part of something called Bayesian analysis and it's been around for centuries now.

From Little Brother by Doctorow, Cory