Negative values of Central Composite Design
Hi! I want to investigate doses of 6 factors at 3 levels - 0, 1, 2 pieces. Without 2 factor interactions confounded with main effects.So I have chosen Central Composite Design - Orthogonal with 9 center points and 53 runs, axial value rotatable - 2.78. Is this the right choice?What confuses me is that the generated design (besides values 0, 1, 2) has values: -1,37841423 and 3,37841423.3,3 is ok, b...