stats.T2: Statistics used in computing and drawing the Hotelling T^2...

In luca-scr/qcc: Quality Control Charts

Statistics used in computing and drawing the Hotelling T^2 chart for subgrouped data

Description

These functions are used to compute statistics required by the T^2 chart.

Usage

stats.T2(data, center = NULL, cov = NULL)

limits.T2(ngroups, size, nvars, conf) 

Arguments

data	the observed data values
center	a vector of values to use for center of input variables.
cov	a matrix of values to use for the covariance matrix of input variables.
ngroups	number of groups
size	sample size
nvars	number of variables
conf	confidence level (0 < conf < 1)

Value

The function stats.T2 returns a list with components:

statistics	a vector of values for the T^2 statistic
means	a matrix of within group means for each variable
center	sample/group center statistic
S	covariance matrix

The function limits.T2 returns a list with components:

control	control limits
prediction	pred.limits

Author(s)

Luca Scrucca

References

Mason, R.L. and Young, J.C. (2002) Multivariate Statistical Process Control with Industrial Applications, SIAM.

Montgomery, D.C. (2013) Introduction to Statistical Quality Control, 7th ed. New York: John Wiley & Sons.

Ryan, T. P. (2011), Statistical Methods for Quality Improvement, 3rd ed. New York: John Wiley & Sons, Inc.

See Also

mqcc, stats.T2.single

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