The CUSUM Procedure

Syntax: INSET Statement

The syntax for the INSET statement is as follows:

  • INSET keyword-list </ options>;

You can use any number of INSET statements in the CUSUM procedure. However, when ODS Graphics is enabled, at most two insets are displayed inside the plot area and at most two are displayed in the chart margins. Each INSET statement produces a separate inset and must follow an XCHART statement. The inset appears on every panel (page) produced by the last XCHART statement preceding it.

Keywords specify the statistics to be displayed in an inset; options control the inset’s location and appearance. A complete description of the INSET statement syntax is given in the section Syntax: INSET and INSET2 Statements of Chapter 17: The SHEWHART Procedure. The INSET statement options are identical in the CUSUM and SHEWHART procedures, but the available keywords are different. The options are listed in Table 17.88. The keywords available with the CUSUM procedure are listed in Table 6.8 to Table 6.11.

Table 6.8: Summary Statistics

Keyword

Description

ARL0

average run length for zero shift

ARLDELTA

average run length for shift of $\delta $

DATA=

arbitrary values from SAS-data-set

N

nominal subgroup size

NMIN

minimum subgroup size

NMAX

maximum subgroup size


Table 6.9: Parameters for One-Sided (Decision Interval) Cusum Scheme

Keyword

Description

DELTA

shift to be detected as multiple of standard error

H

decision interval h as a multiple of standard error

HEADSTART

headstart value $S_{0}$ as a multiple of standard error

K

reference value k

MU0

target mean $\mu _{0}$

SHIFT

shift to be detected in data units

STDDEV

estimated or specified process standard deviation


Table 6.10: Parameters for Two-Sided (V-Mask) Cusum Scheme

Keyword

Description

ALPHA

probability of Type 1 error

BETA

probability of Type 2 error

H

vertical distance between V-mask origin and upper (or lower) arm

K

slope of lower arm of V-mask

SIGMAS

probability of Type 1 error as probability that standard normally distributed variable exceeds a specified value in absolute value


You can use the keywords in Table 6.11 only when producing ODS Graphics output. The labels for the statistics use Greek letters.

Table 6.11: Keywords Specific to ODS Graphics Output

Keyword

Description

UALPHA

probability of Type 1 error

UARLDELTA

average run length for shift of $\delta $

UBETA

probability of Type 2 error

UDELTA

shift to be detected as multiple of standard error

UMU0

target mean $\mu _{0}$

USIGMA

estimated or specified process standard deviation