| carrots | R Documentation |
The damage carrots data set from Phelps (1982) was used by McCullagh and Nelder (1989) in order to illustrate diagnostic techniques because of the presence of an outlier. In a soil experiment trial with three blocks, eight levels of insecticide were applied and the carrots were tested for insect damage.
data(carrots)
A data frame with 24 observations on the following 4 variables.
integer giving the number of carrots with insect damage.
integer giving the total number of carrots per experimental unit.
a numeric vector giving log(dose) values (eight different levels only).
factor with levels B1 to B3
Phelps, K. (1982).
Use of the complementary log-log function to describe doseresponse
relationships in insecticide evaluation field trials.
In R. Gilchrist (Ed.), Lecture Notes in Statistics, No. 14.
GLIM.82: Proceedings of the International Conference on Generalized
Linear Models; Springer-Verlag.
McCullagh P. and Nelder, J. A. (1989) Generalized Linear Models. London: Chapman and Hall.
Eva Cantoni and Elvezio Ronchetti (2001); JASA, and
Eva Cantoni (2004); JSS, see glmrob
data(carrots)
str(carrots)
plot(success/total ~ logdose, data = carrots, col = as.integer(block))
coplot(success/total ~ logdose | block, data = carrots)
## Classical glm
Cfit0 <- glm(cbind(success, total-success) ~ logdose + block,
data=carrots, family=binomial)
summary(Cfit0)
## Robust Fit (see help(glmrob)) ....