IQCC (version 0.7)

cchart.p: p-chart

Description

This function builds p-charts.

Usage

cchart.p(x1 = NULL, n1 = NULL, type = "norm", p1 = NULL, x2 = NULL,
  n2 = NULL, phat = NULL, p2 = NULL)

Arguments

x1

The phase I data that will be plotted (if it is a phase I chart).

n1

A value or a vector of values specifying the sample sizes associated with each group for the phase I data.

type

The type of p-chart to be plotted. The options are "norm" (traditional Shewhart p-chart), "CF" (Cornish Fisher p-chart) and "std" (standardized p-chart). If not specified, a Shewhart p-chart will be plotted.

p1

The data used to estimate the phat (x1 / n1).

x2

The phase II data that will be plotted in a phase II chart.

n2

A value or a vector of values specifying the sample sizes associated with each group for the phase II data.

phat

The estimate of p.

p2

The values corresponding to x2 / n2.

Value

Return a p-chart.

Details

For a phase I p-chart, n1 must be specified and either x1 or p1. For a phase II p-chart, n2 must be specified, plus x2 or p2 and either phat, x1 and n1, or p1 and n1. The Shewhart is based on normal-aprroximation and should be used only for large values of np or n*p (n*p > 6).

References

Montgomery, D.C.,(2008)."Introduction to Statistical Quality Control". Chapter 11. Wiley

Examples

# NOT RUN {
data(binomdata)
attach(binomdata)
cchart.p(x1 = Di[1:12], n1 = ni[1:12])
cchart.p(x1 = Di[1:12], n1 = ni[1:12], type = "CF", x2 = Di[13:25], n2 = ni[13:25])
cchart.p(type = "std", p2 = Di[13:25], n2 = ni[13:25], phat = 0.1115833)

# }