UCHART Statement: ANOM Procedure

Syntax: UCHART Statement

The basic syntax for the UCHART statement is as follows:

  • UCHART response $*$ group-variable;

The general form of this syntax is as follows:

  • UCHART responses $*$ group-variable <(block-variables)><=symbol-variable | ='character'> <options >;

You can use any number of UCHART statements in the ANOM procedure. The components of the UCHART statement are described as follows.

response
responses

identify one or more responses to be analyzed. The specification of response depends on the input data set specified in the PROC ANOM statement.

  • If counts are read from a DATA= data set, response must be the name of the variable containing the counts. For an example, see Creating ANOM Charts for Rates from Group Counts.

  • If rates and numbers of opportunity units are read from a SUMMARY= data set, response must be the common prefix of the appropriate variables in the SUMMARY= data set.

  • If rates, numbers of opportunity units, and decision limits are read from a TABLE= data set, response must be the value of the variable _VAR_ in the TABLE= data set.

A response is required. If you specify more than one response, enclose the list in parentheses. For example, the following statements request distinct ANOM u charts for Defects and Flaws: 

proc anom data=Measures;
   uchart (Defects Flaws)*Sample / groupn=30;
run;

Note that when data are read from a DATA= data set with the UCHART statement, the GROUPN= option (which specifies the number of opportunity units per group) is required.

group-variable

is the variable that identifies groups in the data. The group-variable is required. In the preceding UCHART statement, sample is the group variable.

block-variables

are optional variables that identify sets of consecutive groups on the chart. The blocks are labeled in a legend, and each block-variable provides one level of labels in the legend.

symbol-variable

is an optional variable whose levels (unique values) determine the symbol marker used to plot the rates. Distinct symbol markers are displayed for points corresponding to the various levels of the symbol-variable. You can specify the symbol markers with SYMBOLn statements.

options

enhance the appearance of the chart, request additional analyses, save results in data sets, and so on. The section Summary of Options lists all options by function.