drc (version 3.0-1)

deguelin: Deguelin applied to chrysanthemum aphis

Description

Quantal assay data from an experiment where the insectide deguelin was applied to Macrosiphoniella sanborni.

Usage

data(deguelin)

Format

A data frame with 6 observations on the following 4 variables.

Source

Morgan, B. J. T. (1992) Analysis of Quantal Response Data, London: Chapman \& Hall/CRC (Table 3.9, p. 117).

Details

The log-logistic model provides an inadequate fit.

The dataset is used in Nottingham and Birch (2000) to illustrate a semiparametric approach to dose-response modelling.

References

Notttingham, Q. J. and Birch, J. B. (2000) A semiparametric approach to analysing dose-response data, Statist. Med., 19, 389--404.

Examples

## Log-logistic fit
deguelin.m1 <- drm(r/n~dose, weights=n, data=deguelin, fct=LL.2(), type="binomial")
modelFit(deguelin.m1)
summary(deguelin.m1)

## Loess fit
deguelin.m2 <- loess(r/n~dose, data=deguelin, degree=1)

## Plot of data with fits superimposed
plot(deguelin.m1, ylim=c(0.2,1))
lines(1:60, predict(deguelin.m2, newdata=data.frame(dose=1:60)), col = 2, lty = 2)

lines(1:60, 0.95*predict(deguelin.m2, 
newdata=data.frame(dose=1:60))+0.05*predict(deguelin.m1, newdata=data.frame(dose=1:60), se = FALSE),
col = 3, lty=3)