MathLAB Journal

The Partial Replications of the Central Composite Designs for Spherical Regions

Abstract

Onyishi, Linus Ifeanyi F.C. Eze

Effects of partial replications of the star portion of the Central Composite Design (CCD) on the alternative axial distances were evaluated by comparing the performances of the replicated variations of the CCD in the spherical regions. The fractions of design space graphs (FDSG) of the star-replicated CCDs in the spherical region were plotted as well as the variance dispersion graph (VDG). The replication of the star portion of the CCD improved the prediction variance characteristics of the variations of the CCD in the spherical design regions.