getCC.XBAR: Random Flexible Level Shift Model

In PH1XBAR: Phase I Shewhart X-Bar Chart

Random Flexible Level Shift Model

Description

get Phase I corrected charting constant

Usage

getCC.XBAR(
  m,
  fap0 = 0.05,
  var.est = c("S", "MR"),
  ub.cons = 1,
  method = c("exact", "BA"),
  interval = c(1, 4),
  nsim = 10000,
  nu = m - 1,
  lambda = 1,
  verbose = FALSE
)

Arguments

m	number of subgroups when the data are subgrouped or number of observations when the data are individual.
fap0	nominal False Alarm Probabilty in Phase 1
var.est	'S' - use mean-square-based estimator, 'MR' - use moving-range-based estimator
ub.cons	unbiasing constant
method	'exact' - calculate results using the exact method, 'BA' - calculate results using the Bonfferoni approximation
interval	searching range of charting constants for the exact method
nsim	number of simulation for the exact method
nu	degrees of freedom; When var.est = 'S', the degrees of freedom is that of the chi-squared distribution itself for the variance estimator. When var.est = 'MR', the degrees of freedom is that of the chi-squared distribution approximating to the actual distribution.
lambda	unbiasing constant for the chi-squared distribution approximation. When var.est = 'S', there is no need to do the unbiasing. When var.est = 'MR', the unbiasing constant needs to be used.
verbose	print diagnostic information about fap0 and the charting constant during the simulations for the exact method

Value

Object type double. The corrected charting constant.

Examples

set.seed(12345)

# Calculate the charting constant using 10 simulations and mean-square-based estimator
getCC.XBAR(fap0=0.05, m=20, nsim=10, var.est='S', verbose = TRUE)

# Calculate the charting constant using 10 simulations and moving-range-based estimator
getCC.XBAR(fap0=0.05, m=20, nsim=10, var.est='MR', verbose = TRUE)

PH1XBAR documentation built on June 19, 2025, 5:07 p.m.