budworm {asuR}R Documentation

budworm data

Description

Data from a small experiment on the toxicity to the tobacco budworm

Usage

data(budworm)

Format

A data frame with 12 observations on the following 4 variables.

num.dead
a numeric vector
num.alive
a numeric vector
sex
a factor with levels female male
dose
a numeric vector

Details

Experiment on the toxicity to the tobacco budworm Heliothis virescens of doses of the pyrethoid trans-cypermethrin to which the moths were beginning to show resistance. Batches of 20 moths of each sex were exposed for three days to the pyrethroid and the number in each batch that were dead or knocked down was recorded.

Source

Collette(1991)

References

from MASS p.190; by Venables and Ripley (see also there for suggestions on how to analyse)

Examples

## usage:
data(budworm)

budworm.contr <- rbind("female-male"=c(1,-1))
b.glm <- glm(cbind(num.dead,num.alive) ~ sex*log2(dose),
               family=binomial,
               contrasts=list(sex=mycontr(contr=budworm.contr)),
               data=budworm)

b1.glm <- glm(cbind(num.dead,num.alive) ~ sex*I(log2(dose)-3),
               family=binomial,
               contrasts=list(sex=mycontr(contr=budworm.contr)),
               data=budworm)

b2.glm <- glm(cbind(num.dead,num.alive) ~ sex + I(log2(dose)-3),
               family=binomial,
               contrasts=list(sex=mycontr(contr=budworm.contr)),
               data=budworm)

[Package asuR version 0.08-24 Index]