BOXCHART Statement: ANOM Procedure

Example 4.1 ANOM Boxcharts with Unequal Group Sizes

See ANMBXEX1 in the SAS/QC Sample LibraryConsider the example described in Creating ANOM Boxcharts from Response Values. Suppose that four of the 10 measurements were missing for the third and fourth labeler positions. The following statements create a SAS data set named LabelDev2, which contains the resulting deviation measurements:

data LabelDev2;
   input Position @;
   do i = 1 to 5;
      input Deviation @;
      output;
   end;
   drop i;
   datalines;
1  -0.0239  -0.0285  -0.0300  -0.0043  -0.0362
1  -0.0422  -0.0014  -0.0647   0.0094  -0.0016
2  -0.0201  -0.0273   0.0227  -0.0332   0.0366
2   0.0438   0.0556   0.0098   0.0564   0.0182
3  -0.0073   0.0285    .        .      -0.0139
3    .       0.0357   0.0235    .      -0.0020
4   0.0669   0.1073    .        .       0.0755
4    .       0.0561   0.0899    .       0.0530
5   0.0368   0.0036   0.0374   0.0116  -0.0074
5   0.0250  -0.0080   0.0302  -0.0015  -0.0464
6   0.0049  -0.0384  -0.0204  -0.0049  -0.0120
6   0.0071  -0.0308   0.0017  -0.0285  -0.0070
;

The following statements create the ANOM chart shown in Output 4.1.1:

ods graphics off;
title 'Analysis of Label Deviations';
proc anom data=LabelDev2;
   boxchart Deviation*Position;
   label Deviation = 'Mean Deviation from Center (mm)';
   label Position  = 'Labeler Position';
run;

Output 4.1.1: ANOM Chart with Unequal Group Sizes

Note that the decision limits are automatically adjusted for the varying group sizes. The legend reports the minimum and maximum group sizes.