Sample of egg weights on 24 consecutive days

Usage

data("goulden.eggs")

Format

A data frame with 240 observations on the following 2 variables.

day: day
weight: weight

Details

Data are the weights of 10 eggs taken at random on each day for 24 days. Day 1 was Dec 10, and Day 24 was Jan 2.

The control chart for standard deviations shows 4 values beyond the upper limits. The data reveals a single, unusually large egg on each of these days. These are almost surely double-yolk eggs.

Source

Cyrus H. Goulden (1952). Methods of Statistical Analysis, 2nd ed. Page 425.

References

None.

Examples

if (FALSE) { # \dontrun{

library(agridat)
data(goulden.eggs)
dat <- goulden.eggs

libs(qicharts)
# Figure 19-4 of Goulden. (Goulden uses 1/n when calculating std dev)
op <- par(mfrow=c(2,1))
qic(weight, x = day, data = dat, chart = 'xbar',
    main = 'goulden.eggs - Xbar chart',
    xlab = 'Date', ylab = 'Avg egg weight' )
qic(weight, x = day, data = dat, chart = 's',
    main = 'goulden.eggs - S chart',
    xlab = 'Date', ylab = 'Std dev egg weight' )
par(op)

} # }