qcs.hat.cpm: Process capability index (estimate Cpm)

In mflores72000/qcr: Quality Control Review

Process capability index (estimate Cpm)

Description

Estimate "Cpm" using the method described by Kerstin Vannman(2001).

Usage

qcs.hat.cpm(
  object,
  limits = c(lsl = -3, usl = 3),
  target = NULL,
  mu = 0,
  std.dev = 1,
  nsigmas = 3,
  k0 = 1,
  alpha = 0.05,
  n = 50,
  contour = TRUE,
  ylim = NULL,
  ...
)

Arguments

object	qcs object of type "qcs.xbar" or "qcs.one".
limits	A vector specifying the lower and upper specification limits.
target	A value specifying the target of the process. If it is NULL, the target is set at the middle value between specification limits.
mu	A value specifying the mean of data.
std.dev	A value specifying the within-group standard deviation.
nsigmas	A numeric value specifying the number of sigmas to use.
k0	A numeric value. If the capacity index exceeds the k value, then the process is capable.
alpha	The significance level (by default alpha=0.05).
n	Size of the sample.
contour	Logical value indicating whether contour graph should be plotted.
ylim	The "y" limits of the plot.
...	Arguments to be passed to or from methods.

References

Montgomery, D.C. (1991) Introduction to Statistical Quality Control, 2nd ed, New York, John Wiley & Sons.
Vannman, K. (2001). A Graphical Method to Control Process Capability. Frontiers in Statistical Quality Control, No 6, Editors: H-J Lenz and P-TH Wilrich. Physica-Verlag, Heidelberg, 290-311.
Hubele and Vannman (2004). The E???ect of Pooled and Un-pooled Variance Estimators on Cpm When Using Subsamples. Journal Quality Technology, 36, 207-222.

Examples

library(qcr)
data(pistonrings) 
xbar <- qcs.xbar(pistonrings[1:125,],plot = TRUE)
mu <-xbar$center
std.dev <-xbar$std.dev
LSL=73.99; USL=74.01
qcs.hat.cpm(limits = c(LSL,USL),
           mu = mu,std.dev = std.dev,ylim=c(0,1))
qcs.hat.cpm(object = xbar, limits = c(LSL,USL),ylim=c(0,1))

mflores72000/qcr documentation built on July 1, 2023, 9:17 p.m.