budworm.df: Budworm data

In R330: An R package for Stats 330

Description

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

Usage

data(budworm.df)

Format

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

sex

the sex of the budworm

dose

amount of cypermethrin exposed to

s

number of budworms affected

n

total number of budworms

Details

The data come from an 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, D. (1991) Modelling Binary Data. Chapman and Hall, London. p 75

References

Venables, W.N and Ripley, B. (2002) Modern Applied Statitics with S, Springer, New York.

Examples

data(budworm.df)
bugs.glm<-glm(s/n~sex+dose,family=binomial,weights=n,data=budworm.df)
summary(bugs.glm)

Example output

Loading required package: s20x
Loading required package: leaps
Loading required package: rgl
Loading required package: lattice
Warning messages:
1: In rgl.init(initValue, onlyNULL) : RGL: unable to open X11 display
2: 'rgl_init' failed, running with rgl.useNULL = TRUE 
3: .onUnload failed in unloadNamespace() for 'rgl', details:
  call: fun(...)
  error: object 'rgl_quit' not found 

Call:
glm(formula = s/n ~ sex + dose, family = binomial, data = budworm.df, 
    weights = n)

Deviance Residuals: 
    Min       1Q   Median       3Q      Max  
-2.5566  -1.3326   0.3384   1.1254   1.8838  

Coefficients:
            Estimate Std. Error z value Pr(>|z|)    
(Intercept) -1.16607    0.26155  -4.458 8.26e-06 ***
sex         -0.96855    0.32954  -2.939  0.00329 ** 
dose         0.15996    0.02341   6.832 8.39e-12 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

(Dispersion parameter for binomial family taken to be 1)

    Null deviance: 124.876  on 11  degrees of freedom
Residual deviance:  27.968  on  9  degrees of freedom
AIC: 64.078

Number of Fisher Scoring iterations: 5

R330 documentation built on May 2, 2019, 2:12 p.m.