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, the conditional probability that the card is a face card given that it’s a king is 1, or 100 percent.

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