gompertzd provides a way of specifying the derivative of the Gompertz function
as a dose-response model.
Usage
gompertzd(fixed = c(NA, NA), names = c("a", "b"))
Arguments
- fixed
numeric vector. Specifies which parameters are fixed and at what value they are fixed.
NAs for parameters that are not fixed.
- names
a vector of character strings giving the names of the parameters (should not contain ":").
The default is (notice the order): a, b.
Value
A list containing the model function, the self starter function
and the parameter names.
Details
The derivative of the Gompertz function is defined as
$$f(x) = a \exp(bx-a/b(\exp(bx)-1))$$
For \(a>0\) and \(b\) not 0, the function is decreasing, equaling \(a\) at \(x=0\)
and approaching 0 at plus infinity.
