Generalised logistic function

The generalised (generalized) logistic function or curve, also known as Richards' curve, originally developed for growth modelling, is an extension of the logistic or sigmoid functions, allowing for more flexible S-shaped curves: The generalised (generalized) logistic function or curve, also known as Richards' curve, originally developed for growth modelling, is an extension of the logistic or sigmoid functions, allowing for more flexible S-shaped curves: where Y {displaystyle Y} = weight, height, size etc., and t {displaystyle t} = time.