A small count data set involving 414 machinists from a three months study, of accidents around the end of WWI.
data(machinists)
A data frame with the following variables.
The number of accidents
Observed frequency, i.e., the number of machinists with that many accidents
The data was collected over a period of three months. There were 414 machinists in total. Also, there were data collected over six months, but it is not given here.
Greenwood, M. and Yule, G. U. (1920). An Inquiry into the Nature of Frequency Distributions Representative of Multiple Happenings with Particular Reference to the Occurrence of Multiple Attacks of Disease or of Repeated Accidents. Journal of the Royal Statistical Society, 83, 255--279.
# NOT RUN {
machinists
mean(with(machinists, rep(accidents, times = ofreq)))
var(with(machinists, rep(accidents, times = ofreq)))
# }
# NOT RUN {
barplot(with(machinists, ofreq),
names.arg = as.character(with(machinists, accidents)),
main = "Machinists accidents",
col = "lightblue", las = 1,
ylab = "Frequency", xlab = "accidents")
# }
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