Davis distribution


In statistics, the Davis distributions are a family of continuous probability distributions. It is named after Harold T. Davis, who in 1941 proposed this distribution to model income sizes.. It is a generalization of the Planck's law of radiation from statistical physics.

Definition

The probability density function of the Davis distribution is given by
where is the Gamma function and is the Riemann zeta function. Here μ, b, and n are parameters of the distribution, and n need not be an integer.

Background

In an attempt to derive an expression that would represent not merely the upper tail of the distribution of income, Davis required an appropriate model with the following properties