vMask.method1: Method 1 for V-Mask Implementation: Using mu0, d and theta

In vMask: Detect Small Changes in Process Mean using CUSUM Control Chart by v-Mask

Description

The V-mask method in vMask Package, is considered on the basis of variety of situations/information by different functions. One of these functions is vMask.method1 which can plot the V-mask based on μ_0, d and θ.

Usage

vMask.method1(data, mu0 = mean(data), d, theta = 14, sleep = 1)

Arguments

data	Type of inputted data must be a matrix with dim=c(m,n), in which m is size of samples and n is size of each subsample. Meanwhile, data can be a numerical vector where its elements are sub-sample means.
mu0	Target value for process mean, with default mean(data).
d	Suppose that O is the latest cumulative sum point (which duty of the V-mask is checking this point), and also P is the junction points of V-mask arms. Now, h is the distance between two points O and P.
theta	half of the angle formed by the V-mask arms (in degrees).
sleep	Sleeping time (in second) of the program between showing figures. This time needs for see the result of checking i-th point on CUSUM control chart by V-mask. Also, if sleep="PressEnter", then the user must press key [Enter] in 'R Console' window to continue/check the next cumulative summation point on chart with V-mask.

Details

The origin point of the V-Mask is placed over/top of the latest cumulative summation point and past points are examined to see if any fall above or below the arms of the V-mask. As long as all the previous points lie between the sides of the V-mask, the process is in control. Otherwise (even if one point lies outside) the process is suspected of being out of control.

Value

h	the vertical distance between the origin and the upper (or lower) arm of V-mask.
c	A vector of the cumulative differences between statistic (mean) values and the mean target value; i.e. c=(c_1, ..., c_m) where c_i=∑_{j=1}^{i} (\bar{x}_j - μ_0) .
OutControl	The number of Out-of-control points in CUSUM chart.
InControl	The number of In-control points in CUSUM chart.

See Also

vMask.method2

Examples

### Example 1: (Data matrix)
m = 10	#The size of samples
n = 3 	#The size of each subsample
set.seed(123)
Data = matrix(rnorm(m*n, 1.5,3), nrow=m)
head(Data, 4)

vMask.method1( data=Data, d=4, theta=30, sleep="PressEnter")
vMask.method1( data=Data, d=4, theta=30, sleep=0)    #Check with sleep=1
vMask.method1( data=Data, d=4.5, theta=30, sleep=0)
vMask.method1( data=Data, mu0=0, d=4.5, theta=45, sl=0)

### Example 2: (Vectoral data) 
set.seed(123)
vMask.method1( data=rnorm(20, 1,2), mu0=0, d=8, theta=45, sl=0)

vMask documentation built on May 1, 2019, 10:21 p.m.