R: Leaf length of barley

leaflength {drc} | R Documentation

## Leaf length of barley

### Description

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

### Usage

    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

    ## 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")

[Package drc version 3.0-1 Index]