Noncentral composite designs

Second-order designs are constructed by adding a second two-level design to an initial 2(k) or 2(k=p) experiment. I label such designs as noncentral c o,composite designs since they are composed of two designs with different c enters. The location of the second block can be determined following analys is of the initial experiment. Noncentral composite designs provide an attra ctive alternative to tile popular central composite designs when the locati on of interest shifts following an initial two-level design, An alternative family of asymmetric composite designs is also considered. The methodology is illustrated via a paper-helicopter experiment.