ON MODIFIED SECOND ORDER SLOPE ROTATABLE DESIGNS USING INCOMPLETE BLOCK DESIGNS WITH UNEQUAL BLOCK SIZES

B. Re. Victorbabu (India)

Received August 18, 2006; Revised June 18, 2007

Abstract

In this paper, new method of constructions of modified second order slope rotatable designs (SOSRD) using symmetrical unequal block arrangements (SUBA) with two unequal sizes and pairwise balanced designs (PBD) are suggested. In this method the number of design points required is in some cases less than the number required in Victorbabu [11] method of construction of modified SOSRD using balanced incomplete block designs. Further, a new method of construction of three level modified SOSRD using incomplete block designs with unequal block sizes is presented. The modified SOSRD can be viewed as SOSRD constructed with the technique of augmentation of second order rotatable design (SORD) using incomplete block designs with unequal block sizes to SOSRD. These designs are useful in parts to estimate responses and slopes with spherical variance functions.

Keywords and phrases: modified second order response surface designs, modified second order slope rotatable designs.