drc (version 0.8-2)

FA: Effect of Ferulic Acid on growth of ryegrass

Description

A single dose-response curve.

Usage

data(FA)

source

Inderjit and J. C. Streibig, and M. Olofsdotter (2002) Joint action of phenolic acid mixtures and its significance in allelopathy research, Physiologia Plantarum, 114, 422--428, 2002.

Details

The data are part of a study to investigate the joint action of phenolic acids on root growth inhibition of perennial ryegrass (Lolium perenne L). MM is the concentration of ferulic acid in mM, and MEANLR is the root length of perennial ryegrass.

Examples

## Displaying the data set
FA

## Fitting a four-parameter logistic regression 
## with user-defined parameter names
model1 <- multdrc(MEANLR~MM, data=FA, 
fct = l4(names = c("Slope", "Lower Limit", "Upper Limit", "ED50")))

## Getting a summary of the fit
summary(model1)


## Fitting a model with very small dose values
FA2 <- FA
FA2[,2] <- FA2[,2]/1e6
model2 <- multdrc(MEANLR~MM, data=FA2)

## Removing the model objects
rm(model1, model2, FA2)