growthmodels (version 1.3.1)

blumberg: Blumberg growth model

Description

Computes the Blumberg growth model and its inverse $$ y(t) = \frac{\alpha * (t + t_0)^m}{w_0 + (t + t_0)^m}$$

Usage

blumberg(t, alpha, w0, m, t0 = 0)
blumberg.inverse(x, alpha, w0, m, t0 = 0)

Arguments

t

time

alpha

upper asymptote

w0

a reference value at t = t0

m

slope of growth

t0

time shift (default 0)

x

size

Author

Daniel Rodriguez

References

A. Tsoularis and J. Wallace, "Analysis of logistic growth models.," Math Biosci, vol. 179, no. 1, pp. 21-55, Jul. 2002.

Examples

growth <- blumberg(0:10, 10, 2, 0.5)

# Calculate inverse function
time <- blumberg.inverse(growth, 12, 2, 0.5)