An Etymological Dictionary of Astronomy and Astrophysics

A probability distribution for independent events for which there are only two possible outcomes i.e., success and failure.

The probability of x successes in n trials is: P(x) = [n!/x!(n - x)!] p^x.q^{n - x}, where p is the probability of success and q = 1 - p the probability of failure on each trial. These probabilities are given in terms of the → binomial theorem expansion of (p + q)ⁿ.

See also: → binomial; → distribution.