Example of Create 2-Level Factorial Design (Specify Generators)

Interpret the results

The first table gives a summary of the design. With 9 factors, a full factorial design has 512 runs. Because resources are limited, the engineer created the 1/16^th fraction design with 32 runs.

The resolution of a design that has not been blocked is the length of the shortest word in the defining relation. In this example, the shortest words in the defining relation have four letters so the resolution is IV. In a resolution IV design, some main effects are confounded with 3-way interactions, but not with any 2-way interactions or other main effects. Because 2-way interactions are confounded with each other, the engineer has to evaluate any significant interactions further to define their nature.

The alias table shows that no main effects are aliased with any two-factor interactions and that 21 of the two-factor interactions are aliased with other 2-factor interactions. The design does not alias any of the two-factor interactions that involve factors A and B with any other two-factor interactions.