Piston rings for an automotive engine are produced by a forging process.
The inside diameter of the rings manufactured by the process is measured on
25 samples, each of size 5, drawn from a process being considered 'in
control'.
Format
A data frame with 200 observations on the following 3 variables.
diameter
a numeric vector
sample
sample ID
trial
trial sample indicator (TRUE/FALSE)
References
Montgomery, D.C. (1991) Introduction to Statistical
Quality Control, 2nd ed, New York, John Wiley & Sons, pp. 206–213