drc (version 1.3-0)

MM: Michaelis-Menten model

Description

'MM' specifies the Michaelis-Menten model or the shifted Michaelis-Menten model for modelling enzyme kinetics, weed densities etc.

Usage

MM(fixed = c(NA, NA, 0), names = c("Vm", "K", "y0"))

Arguments

fixed

numeric vector. Specifies which parameters are fixed and at what value they are fixed. NAs for parameter that are not fixed.

names

a vector of character strings giving the names of the parameters (should not contain ":"). The order of the parameters is: Vm, K, y0 (see under 'Details').

Value

• An object containing with all components needed in multdrc.

Details

The model is given by the expression $$f(x) = y0 + \frac{Vm x}{K + x}$$ It is a three-parameter model.

Examples

ctl <- data.frame(list(conc=c(0,0,0), rate=c(55,60,65), state=c('ctl','ctl','ctl')))
pu <- rbind(Puromycin, ctl)

model1<-multdrc(rate~conc, state, 
collapse=data.frame(state,state,1), 
data=pu, fct=MM(fixed=c(NA,NA,NA)))

summary(model1)
plot(model1) 

rm(ctl, pu, model1)