bcl4 {drc} | R Documentation |
'bcl4' provides the five-parameter function, self starter function and names of the parameters.
bcl4(names = c("b", "c", "d", "e", "f"), useDer = FALSE)
names |
a vector of character strings giving the names of the parameters. The default is reasonable. |
useDer |
logical. If TRUE derivatives are supplied, otherwise they are not supplied. Not implemented! |
The Brain-Cousens model is given by the expression
f(x) = c + frac{d-c+fx}{1+exp(b(log(x)-log(e)))}
which is a five-parameter model.
It is a modification of the four-parameter logistic curve to take hormesis into account.
See braincousens
.
This function is for use with the function multdrc
.
Christian Ritz
Brain, P. and Cousens, R. (1989) An equation to describe dose responses where there is stimulation of growth at low doses, Weed Research, 29, 93–96.
The related function bcl3
.
model1 <- multdrc(hormesis[,c(2,1)], fct=bcl4()) anova(model1) plot(model1) rm(model1)