Leaf length of barley

In an experiment barley was grown in a hydroponic solution with a herbicide.

data(leaflength)

Format

A data frame with 42 observations on the following 2 variables.

Dose

a numeric vector

DW

a numeric vector

Details

The dataset exhibits a large hormetical effect.

Source

Nina Cedergreen, Royal Veterinary and Agricultural University, Denmark.

Examples

# NOT RUN {
library(drc)

## Fitting a hormesis model
leaflength.crs4c1 <- drm(DW ~ Dose, data = leaflength, fct = CRS.4c())
plot(fitted(leaflength.crs4c1), residuals(leaflength.crs4c1))

leaflength.crs4c2 <- boxcox(drm(DW ~ Dose, data = leaflength, fct = CRS.4c()),
method = "anova", plotit = FALSE)
summary(leaflength.crs4c2)

## Plottinf fitted curve and original data
plot(leaflength.crs4c2, broken = TRUE, conLevel = 0.001, type = "all", legend = FALSE,
ylab = "Produced leaf length (cm)", xlab = "Metsulfuron-methyl (mg/l)",
main = "Hormesis: leaf length of barley")
# }