| methionine {drc} | R Documentation |
Data consist of average body weight gain of chickens being treated with one of the two methionine sources DLM and HMTBA.
data(methionine)
A data frame with 9 observations on the following 3 variables:
productcontrol, DLM and MHA denoting the treatmentsdosegain
The dataset contains a common control measurement for the two treatments. More examples using this
dataset are found under AR.2 and MM.2.
Kratzer. D. D. and Littell, R. C. (2006) Appropriate Statistical Methods to Compare Dose Responses of Methionine Sources, Poultry Science, 85, 947–954.
## Fitting model with constraint on one parameter met.ar.m1 <- drm(gain~dose, product, data = methionine, fct = AR.3(), pmodels = list(~1, ~factor(product), ~factor(product)), upperl = c(Inf, Inf, 1700, Inf, Inf)) plot(met.ar.m1, xlim=c(0,0.3), ylim=c(1450, 1800)) abline(h=1700, lty=1) summary(met.ar.m1)