Values are arranged in decreasing order of absolute magnitude. Name of the contrast effect is given as the row name of each value. Daniel(1959) uses the data to illustrate the use of half-normal plots. In his words: "We need, of course, some rule of inference that will help us to be objective in judging whether or not the largest effects are real."

penicillin

Format

A data frame with 31 rows and 1 variate:

value

value of contrast for that row

Source

"Use of Half-Normal Plots in Interpreting Factorial Two-Level Experiments", Cuthbert Daniel, Technometrics, Vol. 1, No. 4 (Nov., 1959), pp. 311-341. Daniel cites: Davies, O. L., Editor: Design and Analysis of Industrial Experiments, Second Edition, Oliver and Boyd, London, and Hafner, New York, 1956 as the original.

Details

qqtest(penicillin[1],dist="half-normal") will effect Daniel's plot.