Joint Research Conference

June 24-26, 2014

Abstract:

It is well known that many industrial experiments have split-plot structures. Comparing to completely randomized experiments, split-plot designs are more economical and, thus, have received much attention among researchers. Much work has been done for two-level split-plot designs. In this article, we consider split-plot designs with factors of three or higher and mixed levels, and with both qualitative and quantitative factors. We define word lengths for three different design scenarios that may be important for experimenters. The corresponding word length patterns are defined and the minimum aberration mixed level split-plot orthogonal designs are tabulated for 18-run orthogonal arrays L18 for the three scenarios.