Consider a responsesurface CCD design with center points for

Consider a response-surface CCD design with center points for three factors. We want

to perform the experiment in 3 blocks: two factorial blocks and one axial, with two center

point runs in each of the three blocks. We also want to design to block orthogonal. How many runs to go into reach block with the highest order interaction confounded. b. Value for axial runs so that orthonality of blocking preserved? How many degrees does the design have for pure estimation. How many degrees are used up for blocking?

Solution

How many runs to go into reach block with the highest order interaction confounded

there are 3 runs to go

alue for axial runs so that orthonality of blocking preserved?

3 * 8 = 34

How many degrees does the design have for pure estimation

34-3 = 31

How many degrees are used up for blocking?

3-1 = 2