IQCC (version 1.0)

UchartI: Traditional Shewhart u chart for phase I.

Description

This function builds the traditional Shewhart u chart based on normal approx. for the Poisson-based count data statistic . It is designed for phase I.

Usage

UchartI(x, sizes, par, length)

Arguments

x

The data to be plotted.

sizes

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

par

The sample ratios used to estimate the Poisson parameter(lambda).

length

The length of the data.

Value

• Return a traditional U control chart.

Details

It is important to note that the normal approx. involved is valid only for n.p large. For small n.p , it should be used an "improved u chart" (with non-normal correction) given by the function "UextI" for phase-I or "UextII" for phase II .

See Also

UchartII

Examples

data(moonroof)
attach(moonroof)
UchartI(par=ui[1:17],x=yi[1:17],sizes=ni[1:17],17)