Von Bertalanffy function

The von Bertalanffy growth function (VBGF), or von Bertalanffy curve, is a type of growth curve for a time series and is named after Ludwig von Bertalanffy.

It is a special case of the generalised logistic function.

The growth curve is used to model mean length from age in animals.

[1] The function is commonly applied in ecology to model fish growth[2] and in paleontology to model sclerochronological parameters of shell growth.

[4] It is the solution of the following linear differential equation: The seasonally-adjusted von Bertalanffy is an extension of this function that accounts for organism growth that occurs seasonally.