mistat (version 2.0.4)

mahalanobisT2: Mahalanobis \(T^2\)

Description

Mahalanobis \(T^2\) and Confidence Region

Usage

mahalanobisT2(x, factor.name, response.names = names(x)[!names(x) %in% factor.name], 
conf.level=0.95, compare.to = NA, plot = FALSE)

Value

a list with components:

coord

matrix with transformed coordinates of variables in response.names

mahalanobis

vector containing Lower Control Region, Center and Upper Control Region of Mahalanobis \(T^2\)

mahalanobis.compare

single value, Mahalanobis \(T^2\) of compare.to

Arguments

x

a data frame

factor.name

single character indicating column name of the experiment factor to test, the first level is used as a reference

response.names

vector of characters indicating columns names of the responses

conf.level

confidence level for the Confidence Region

compare.to

a vector of length length(response.names) to be compared to the result in terms of Mahalanobis \(T^2\)

plot

logical, if TRUE also a plot is produced

Author

Daniele Amberti

References

Kenett, R., Zacks, S. with contributions by Amberti, D. Modern Industrial Statistics: with applications in R, MINITAB and JMP. Wiley.

Tsong et al, (1996).

Examples

data(DISS)

mahalanobisT2(DISS[, c("batch", "min15", "min90")], 
              factor.name="batch", 
              conf.level=0.90,
              compare.to=c(15, 15))