Resumen de Unbalanced and Minimal Point Equivalent Estimation Second-Order Split-Plot Designs

Peter A. Parker, Scott M. Kowalski, G. Geoffrey Vining

• Split-plot design structures are used in industrial experiments to minimize costs by reducing the number of resets of hard-to-change factors. Unbalanced designs are considered here for situations where the subplots are costly and the experimental apparatus accommodates an unequal number of runs per whole plot. Construction methods are provided for unbalanced second-order designs and for unbalanced versions of the central-composite and Box-Behnken designs. Where subplot cost approaches whole-plot cost, minimal point designs are proposed and illustrated with a split-plot Notz design.