It is named after Harold T. Davis (1892–1974), who in 1941 proposed this distribution to model income sizes.

(The Theory of Econometrics and Analysis of Economic Time Series).

It is a generalization of the Planck's law of radiation from statistical physics.

The probability density function of the Davis distribution is given by where

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[1]