Robust split-plot designs

In many experimental situations, practitioners are confronted with costly, time consuming, or hard-to-change (HTC) factors. These practical or economic restrictions on randomization can be accommodated with a split-plot design structure that minimizes the manipulation of the HTC factors. Selecting a good design is a challenging task and requires knowledge of the opportunities and restrictions imposed by the experimental apparatus and an evaluation of statistical performance among competing designs. Building on the well-established evaluation criteria for the completely randomized context, we emphasize the unique qualitative and quantitative evaluation criteria for split-plot designs. An example from hypersonic propulsion research is used to demonstrate the consideration of multiple design evaluation criteria. Published in 2007 by John Wiley & Sons, Ltd.