cuckoos R Documentation

## Cuckoo Eggs Data

### Description

Length and breadth measurements of 120 eggs lain in the nests of six different species of host bird.

### Usage

`cuckoos`

### Format

This data frame contains the following columns:

length

the egg lengths in millimeters

species

a factor with levels `hedge.sparrow`, `meadow.pipit`, `pied.wagtail`, `robin`, `tree.pipit`, `wren`

id

a numeric vector

### Source

Latter, O.H. (1902). The eggs of Cuculus canorus. An Inquiry into the dimensions of the cuckoo's egg and the relation of the variations to the size of the eggs of the foster-parent, with notes on coloration, &c. Biometrika i, 164.

### References

Tippett, L.H.C. 1931: "The Methods of Statistics". Williams & Norgate, London.

### Examples

```
print("Strip and Boxplots - Example 2.1.2")

attach(cuckoos)
oldpar <- par(las = 2) # labels at right angle to axis.
stripchart(length ~ species)
boxplot(split(cuckoos\$length, cuckoos\$species),
xlab="Length of egg", horizontal=TRUE)
detach(cuckoos)
par(oldpar)
pause()

print("Summaries - Example 2.2.2")
sapply(split(cuckoos\$length, cuckoos\$species), sd)
pause()

print("Example 4.1.4")
wren <- split(cuckoos\$length, cuckoos\$species)\$wren
median(wren)
n <- length(wren)
sqrt(pi/2)*sd(wren)/sqrt(n)  # this s.e. computation assumes normality
```