Screening designs based on weighing matrices with added two-level categorical factors

Screening designs are used widely in industrial experimentation. They are used to identify factors with the most potential among a large number of factors. In a recent article, Jones and Nachtsheim proposed a new class of designs called definitive screening designs (DSDs), and they later showed how a few categorical factors could be introduced in those designs. In this article, we provide a new general method that can use weighing matrices to construct screening designs with some two-level qualitative factors. The methodology is illustrated through a number of small examples. The generated designs are compared to the designs in the literature and their advantages and disadvantages are discussed.