Generalised Logistic Function

Generalised Logistic Function

The generalised logistic curve or function, also known as Richards' curve is a widely-used and flexible sigmoid function for growth modelling, extending the well-known logistic curve.

where Y = weight, height, size etc., and t = time.

It has six parameters:

• A: the lower asymptote;
• K: the upper asymptote. If A=0 then K is called the carrying capacity;
• B: the growth rate;
• ν>0 : affects near which asymptote maximum growth occurs.
• Q: depends on the value Y(0)
• M: the time of maximum growth if Q=ν