cchart.R: R control chart

In IQCC: Improved Quality Control Charts

Description

This function builds a R control chart.

Usage

cchart.R(x, n, type = "norm", y = NULL)

Arguments

x	The data to be plotted.
n	The sample size.
type	The type of R chart to be plotted. The options are "norm" (traditional Shewhart R chart) and "tukey" (exact R chart). If not specified, a Shewhart R chart will be plotted.
y	The data used in phase I to estimate the standard deviation.

Details

The Shewhart R chart was designed for phase I (at this moment). The limits of the exact R chart are the alpha/2 and 1-alpha/2 quantiles of the R distribution that are calculated as estimated process sd times the quantiles of the relative range (W=R/sigma) distribution.

Value

Return a R control chart.

Author(s)

Daniela R. Recchia, Emanuel P. Barbosa

Examples

data(pistonrings)
attach(pistonrings)
cchart.R(pistonrings[1:25,], 5)
cchart.R(pistonrings[26:40, ], 5, type = "tukey", pistonrings[1:25, ])

IQCC documentation built on May 1, 2019, 10:58 p.m.