Taxonomy of bi-logistic curves
Visualization of the model
The Component Logistic Model
As it turns out, many growth and diffusion processes are actually made
up of several subprocesses. First, let us consider the case of a
system which experiences growth in two discrete growth phases. Then, we
will extend this to an arbitrary number of phases.
Systems with two growth phases follow what we call the ``Bi-logistic'' model . In this model, growth is the sum
of two discrete ``wavelets''
, each of which is a three-parameter logistic:
N(t) = N1(t) + N2(t),
Naturally, we can examine system-level behavior (i.e., N(t)), or we
can decompose the model and examine the behavior of the discrete
components (either N1(t) or N2(t)). In fact, we can plot
N1(t) and N2(t) on the same axes, and moreover we can compare
two disparate wavelets by normalizing them with the Fisher-Pry transform.
Perrin S Meyer