Conditional Optimal Composite Designs

摘要

In this work,optimal composite designs for the second-order response surfaces are considered.Given a first-order design and center points,we seek the axial points which make the composite desing with maximal determinant possible .An MCMC type algorithm is proposed for finding these optimal design points.Based on the symmetric structure of the central composite desings,optimal central composite designs are further constructed via three different optimal criteria (D-,A-,and Ds-optimality).We next consider the minimal-point designs. A novel two-stage method is proposed for finding the minimal-point designs of composite type.These minimal-point designs are obtained and compared with the other small composite designs based upon D-effciency. It is shown that although these minimal-point designs are not necessary optimal,they have reasonably high D-efficiencies in general.