# Gamma distribution

From Glossary of Meteorology

## gamma distribution

A continuous random variable where β and for p > 0.

*x*is said to have a gamma distribution if the range of*x*consists of all positive real numbers and if*x*possesses a density function*f*(*x*) that satisfies the equation*p*are positive numbers and where Γ is the gamma function defined by the integralThe mean of the density function is β

*p*, and the standard deviation is β(*p*)^{½}. The gamma distribution, which is a special case of the Pearson distribution, is skewed to the right. In meteorology, scalar multiples of the gamma distribution are used to represent size distributions of cloud drops.*See*skewness.

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