Phase I Shewhart X-Bar Chart.

Overview

The purpose of PH1XBAR is to build three types of Phase I Shewhart control charts:

1. Phase I Shewhart X-bar control chart with a balanced one-way random effects model (doi:10.1002/qre.2793).

2. Phase I Shewhart individual control chart for the iid case (doi:10.1080/08982112.2021.1878220).

3. Phase I individual control chart with an ARMA model.

Installation

Install from CRAN

PH1XBAR is published on CRAN, so we recommend users installing it in a regular way as follows

install.packages("PH1XBAR")

Install from GitHub

PH1XBAR is still under development, so if users are more interested in the experimental version, there is an alternative installation through Github as follows

install.packages("devtools")
devtools::install_github("bolus123/PH1XBAR")

Note that for Windows users, Rtools may need to be installed in advance. Please choose the right version of Rtools which is corresponding to your R and Rstudio. The detailed instruction is introduced: https://cran.r-project.org/bin/windows/Rtools/

For Mac and Linux users, please follow the instruction: https://www.r-project.org/nosvn/pandoc/devtools.html

Install from local

Users can also download our release, PH1XBAR_x.y.z.tar.gz, from our homepage on CRAN or Github and then install it from your local path as follows

install.packages('path_to_file/PH1XBAR_x.y.z.tar.gz', repos = NULL, type="source")

Usage

Before using any functions, PH1XBAR may need to be loaded into R

library(PH1XBAR)

PH1XBAR provides a function to build Phase I X-bar chart with variance components model as follows

data(grinder_data)
PH1XBAR(grinder_data)

Notice that the variance estimator in the control chart must be S or MR. Also, PH1XBAR provides a function to get the corrected charting constant as follows

# S-based estimator involved
getCC.XBAR(FAP0 = 0.1, m = 30, var.est = 'S')

# MR-based estimator involved
getCC.XBAR(FAP0 = 0.1, m = 30, var.est = 'MR')

PH1XBAR provides a function to build Phase I individual chart with an ARMA model as follows

data(preston_data)

# using the default setting whose FAP0 = 0.1
PH1ARMA(preston_data)

# using known parameters with FAP0 = 0.1
PH1ARMA(preston_data, case = 'K')

PH1XBAR provides a function to get the corrected charting constant for the ARMA model as follows

# Calculate the charting constant using FAP0 of 0.05, and 50 observations
getCC.ARMA(FAP0=0.05, n=50)

More details are on the manual.