A factorial experiment is the simultaneous manipulation of factors at different levels to see their effect on some desired result. A factorial experiment could be ‘a full factorial’ or it could be a ‘fractional factorial’ experiment. If the experiment is fractionated, the practitioner gives up something in the sense that main effects are aliased with interactions, or interactions are aliased with other interactions, and so forth. A full fractional factorial experiment has none of the aliasing, but it cost more because you have to run more experimental trials.
