Generalised logistic function (Richards' curve)


A logistic function or logistic curve is a common “S” shape (sigmoid curve) The generalized logistic curve or function, also known as Richards’ curve is a widely-used and flexible sigmoid function for growth modelling, extending the logistic function.

Related formulas


Y(t)weight, height, size etc. (dimensionless)
A the lower asymptote (dimensionless)
Kthe upper asymptote. If A=0 then K is called the carrying capacity (dimensionless)
Qdepends on the value Y(0) (dimensionless)
Bthe growth rate (dimensionless)
ttime (dimensionless)
Mthe time of maximum growth if Q=ν (dimensionless)
vν>0 : affects near which asymptote maximum growth occurs. (dimensionless)