conditional probability

noun

1. Statistics, Mathematics. the probability that an event will occur under the condition that another event occurs first: equal to the probability that both will occur divided by the probability that the first will occur.

conditional probability

noun

1. statistics the probability of one event, A, occurring given that another, B, is already known to have occurred: written P ( A|B ) and equal to P ( A and B )| P ( B )

Word History and Origins

Origin of conditional probability¹

First recorded in 1960–65

Example Sentences

Bayes’ theorem is a statement about conditional probability—the probability of an event given other known conditions.

From Scientific American

This conclusion is based on a faulty understanding of life expectancy, which is a conditional probability of surviving to a given age.

From Washington Post

We model each conditional probability distribution as follows:

From Nature

However, if it’s known somehow that the person chosen is over six feet four inches tall, then the conditional probability that he or she also weighs more than 250 pounds is considerably higher.

From Literature

The attraction of Bayes's theorem, as Silver presents it, is that it concerns conditional probability: the probability that a theory or hypothesis is true if some event has happened.

From The Guardian