Page 275 - Six Sigma Demystified

Part 3 s i x s i g m a to o l s 255

for each factor at (real) experimental units of (–50, 50). The design array is
shown in standard order with experimental response column added for use in
the “Interpretation” section below (data provided are generated by IQF Six
Sigma Black Certification Exam Study Guide, available at www.qualityamerica
.com):

A B C D E F Response
–50 –50 –50 50 50 50 –108,154
50 –50 –50 –50 –50 50 –43,493.8
–50 50 –50 –50 50 –50 –46,565.2
50 50 –50 50 –50 –50 –153,947
–50 –50 50 50 –50 –50 –43,490.4
50 –50 50 –50 50 –50 –108,146
–50 50 50 –50 –50 50 –153,947
50 50 50 50 50 50 –46,558.7
–50 –50 –50 50 50 50 –108,154
50 –50 –50 50 50 50 –43,493.4
–50 50 –50 –50 50 –50 –46,562
50 50 –50 50 –50 –50 –153,947
–50 –50 50 50 –50 –50 –43,492.8
50 –50 50 –50 50 –50 –108,149
–50 50 50 –50 –50 50 –153,942
50 50 50 50 50 50 –46,564.5

Excel

Using Black Belt XL Add-On
Use New Chart\Designed Experiment to generate a new design. Specify factor
labels, factor type, and experimental values for each factor. Select Terms and
then select only the main factors to generate a screening design. Choose from
the list of designs, and optionally choose Randomize Runs and add Design Rep-
licates and Center Point.
Using the preceding example, the fractional factorial–Taguchi L8 screening
design is chosen with Design Replicates set to 2 to produce a design similar to
Minitab’s shown above.