Nearly A-and E-optimal orthogonally blocked designs for Scheffe's quadratic mixture model with three components

Prescott et al. (technometrics 78: 268-276,1993) proposed d-optimal orthogonally blocked designs in two blocks for scheffé's quadratic mixture model with four components. chan and sandhu (j.appl.statist.26 (1):19-34,1999) discussed the properties of d-,a- and e-optimal designs for scheffe's quadratic mixture model in three components. prescott (comm.stat.theory methods,27(10):2259-2580,1998) introduced nearly d-optimal orthogonally blocked designs for scheffé's quadratic mixture model in three and four components. in this paper,we propose nearly a- and eoptimal orthogonally blocked designs in two blocks for scheffé's quadratic mixture model,in three components. the robustness of nearly optimal orthogonally blocked designs,with respect to d-,aand e-optimality criteria,is checked. © pakistan academy of sciences.