OPTIMAL RESPONSE SURFACE DESIGNS IN THE PRESENCE OF DISPERSION EFFECTS model.The D-and I-efficiencies of the standard de- the Cubi sign are again small in the severe dispersion effects For First-Order Model variance t to -0-4 A similar conclusion can be made for the -optimal designs,except the runs are allocated to the chosen 10.0095.1687.3661.3047.8231.95 the D more 19 the hom ogeneous variance case.and hence the stan dard design is extremely practical in this case The em 100.0089.0572.6946.9931.9317.35 and suggest that choosing a design closer to the Interaction Model is de Fortunately,for se rsion effects D-Optimal tothe magnitude of the dis and her Efficiency 10.00100.00100.0079.9957.743.33 Inverse Quadratic-Inverse Quadratic cture the lar ce is in the design A55 sown in Tab 7,fo Efficiency 100.0093.3377.4849.9331.9912.12 m the factori Second-Order Model severe disperson enects,both the D-and 22221-22-1-2220220220 -efficiencies of the standard design in thes severe Efficiency 85.0688.0790.3089.4989.0588.72 d for change 8o 2222228 240140 With the interact nodel the shift of runs t 21经1 the edge points and then the design center is more radual and both the l )and /-optimal designs are Efficiency 100.0097.2594.1791.8586.2979.17 ffects.The Dd gn are not as low as for the first-order model with of the /-eth ency for For the interaction model.the standard design is D-optimal for mild dispersion effects,and for severe stil ude the theoptimal d of the optimal designs,the shift of runs to the loca sign places few runs at the factorial locations Vol.29.No.1.January 1997 Journal of Quality Technology Reproduced with permission of the copyright owner.Further reproduction prohibited without permission.Reproduced with permission of the copyright owner. Further reproduction prohibited without permission