We're designing a trial to test four factors (call them
D) for an experiment. Each factor has two levels:
+ of factor
A is believed to lead to better results and the
- of factor
B is also believed to lead to better results. We know nothing about
D, nor whether any interaction effects exist or not.
We want to get the following goals:
- Find the combination of factors to get the best result.
- Build a model containing
Dto predict the result of experiments. (This requires that
Bshould still be in this design)
How can we get a fractional factorial design based on our prior knowledge of the effects of