pistonrings: Piston rings data
In luca-scr/qcc: Quality Control Charts

pistonrings

R Documentation

Piston rings data

Description

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, for the control phase I, when preliminary samples from a process being considered 'in control' are used to construct control charts. Then, further 15 samples, again each of size 5, are obtained for phase II.

Usage

data(pistonrings)

Format

A data frame with 200 observations on the following 3 variables.

diameter: a numeric vector
sample: sample ID
trial: preliminary sample indicator (TRUE/FALSE)

References

Montgomery, D.C. (1991) Introduction to Statistical Quality Control, 2nd ed, New York, John Wiley & Sons, pp. 206–213

Examples

data(pistonrings)
describe(pistonrings, by = trial)
boxplot(diameter ~ trial, data = pistonrings)
plot(diameter ~ sample, data = pistonrings, cex=0.7)
with(pistonrings, lines(tapply(diameter,sample,mean)))

luca-scr/qcc documentation built on Feb. 25, 2023, 3:33 p.m.