mqcs.t2 {qcr}

Function to plot t2 Hotelling chart

Description

This function is used to compute statistics required by the t2 chart.

Usage

mqcs.t2(x, ...)

## Default S3 method:
mqcs.t2(
  x,
  data.name = NULL,
  limits = NULL,
  Xmv = NULL,
  S = NULL,
  colm = NULL,
  alpha = 0.01,
  phase = 1,
  method = "sw",
  plot = FALSE,
  ...
)

## S3 method for class 'mqcd'
mqcs.t2(
  x,
  limits = NULL,
  Xmv = NULL,
  S = NULL,
  colm = NULL,
  alpha = 0.01,
  phase = 1,
  method = "sw",
  plot = FALSE,
  ...
)

Arguments

x

an R object (used to select the method). See details.

...

arguments passed to or from methods.

data.name

a string that specifies the title displayed on the plots. If not provided it is taken from the name of the object's data.

limits

a two-values vector specifying the control limits.

Xmv

is the mean vector. It is only specified for Phase II or when the parameters of the distribution are known.

S

is the sample covariance matrix. It is only used for Phase II or when the parameters of the distribution are known.

colm

is the number of samples (m) and it is only used in Hotelling control chart for Phase II

alpha

it is the the significance level (0.01 for default)

phase

Allows to select the type of UCL to use. Only values of phase = 1 or 2 are allowed.

method

is the method employed to compute the covatiance matrix in the individual observation case. Two methods are used "sw" for compute according to (Sullivan,Woodall 1996a) and "hm" by (Holmes,Mergen 1993)

plot

a logical value indicating that it should be plotted.

Author(s)

Edgar Santos-Fernandez

Examples

##
##  Continuous data 
##
library(qcr)
data(dowel1)
str(dowel1)
data.mqcd <- mqcd(dowel1)
res.mqcs <- mqcs.t2(data.mqcd)
summary(res.mqcs)
plot(res.mqcs, title =" Hotelling Control Chart for dowel1")

data(archery1)
str(archery1)
data.mqcd <- mqcd(archery1)
res.mqcs <- mqcs.t2(data.mqcd)
summary(res.mqcs)
plot(res.mqcs, title =" Hotelling Control Chart for archery1")