stats.c: Functions to plot Shewhart c chart

In qcc: Quality Control Charts

Description

Statistics used in computing and drawing a Shewhart c chart.

Usage

stats.c(data, sizes)
sd.c(data, sizes, ...)
limits.c(center, std.dev, sizes, conf)

Arguments

data	the observed data values
center	sample/group center statistic.
sizes	samples sizes.
std.dev	within group standard deviation.
conf	a numeric value used to compute control limits, specifying the number of standard deviations (if conf > 1) or the confidence level (if 0 < conf < 1).
...	further arguments are ignored.

Value

The function stats.c returns a list with components statistics and center.

The function sd.c returns std.dev the standard deviation of the statistic charted.

The function limits.c returns a matrix with lower and upper control limits.

Author(s)

Luca Scrucca

References

Montgomery, D.C. (2005) Introduction to Statistical Quality Control, 5th ed. New York: John Wiley & Sons.
Wetherill, G.B. and Brown, D.W. (1991) Statistical Process Control. New York: Chapman & Hall.

See Also

qcc

qcc documentation built on May 2, 2019, 9:15 a.m.