XploRe Help : spccusum2

Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Library:	spc
See also:	spccusum2c spccusum2arl

Quantlet:		spccusum2
Description:		graphical representation of a two-sided CUSUM chart for given data, critical value and reference value k

Reference(s):

Page, E.S. (1954). Continuous inspection schemes. Biometrika 41: pp. 100-115. Lucas, J.M. (1976). The design and use of V-mask control schemes. Journal of Quality Technology 8: pp. 1-12. Lucas, J.M. and Crosier, R.B. (1982). Fast initial response for cusum quality-control schemes: Give your cusum a headstart, Technometrics 24: pp. 199-205.

Usage:	`spccusum2(k, c, observed)`
Input:
	`k`	scalar, reference value. It must be positive and be expressed as a multiple of the standard error.
	`c`	scalar, critical value
	`observed`	n x 1 vector of user-defined data

Note:

includes in-control ARL computation

Example:

; A two-sided CUSUM chart for 100 pseudorandom variables ; with normal distribution where the first 80 observations ; have mean = 0, the next 20 have mean = 1. The chart ; parameters are k = 0.5 and in-control ARL = 300: library("spc") mean = #(matrix(80) .* 0, matrix(20) .* 1) randomize(31) observed = normal(100) + mean c = spccusum2c(300,.5,50) spccusum2( .5, c, observed)

Result:

Display showing a two-sided CUSUM chart. An alarm is signaled
at t = 88.

Author: S. Knoth, 20011008 license MD*Tech