Poisson distribution


Pois·​son distribution pwä-ˈsōⁿ- How to pronounce Poisson distribution (audio)
: a probability density function that is often used as a mathematical model of the number of outcomes obtained in a suitable interval of time and space, that has its mean equal to its variance, that is used as an approximation to the binomial distribution, and that has the form {latex}f(x) = \frac{e^{-\mu}\mu^{x}}{{x!}}{/latex} where μ is the mean and x takes on nonnegative integral values

Word History


Siméon D. Poisson †1840 French mathematician

First Known Use

1922, in the meaning defined above

Time Traveler
The first known use of Poisson distribution was in 1922

Dictionary Entries Near Poisson distribution

Cite this Entry

“Poisson distribution.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Poisson%20distribution. Accessed 4 Dec. 2023.

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