Game Development Reference
Cleanroom Combinatorial Tables
Cleanroom combinatorial tables will not necessarily be “pairwise�? combinatorial
tables. The number of tests to be created is determined by the test designer and the
values for each test will be chosen on the basis of their frequency of use rather than
whether or not they satisfy one or more necessary value pairs.
To produce Cleanroom combinatorial tables, assign usage probabilities to the test values
of each parameter. The probabilities of the set of values associated with a single para-
meter must add up to 100%.
To illustrate how this is done, revisit the parameter and value choices for the HALO
Advanced Controls table you completed in Figure 10.26. The test values for each para-
meter are listed below with the default values identified.
Look Sensitivity : 1, 3 (default), 10
Invert Thumbstick : Yes, No (default)
Controller Vibration : Yes (default), No
Invert Flight Control : Yes, No (default)
Auto Center : Yes, No (default)
Next, usage percentages need to be determined for each of the table's parameters. If
you are considering testing against more than one player profile, you can make a sep-
arate usage table for each parameter with a column of usage percentages for each of
the profiles you intend to test. Figures 12.3 through 12.7 show multiple profile usage
tables for each of the five HALO Advanced Controls parameters you will incorporate
in your Cleanroom combinatorial table.
Please, don't send emails to explain why any of these percentages are wrong. We have only
presented a variety of numbers to illustrate differences between user types based on personal expe-
rience. If you have better data gathered through scientific means, then that is what you should be
using. If these numbers don't make sense to you, then consider them “for entertainment purposes
only�? as you continue through the examples in this chapter.
Figure 12.3 Look Sensitivity values with usage percentages.