Response surface designs
are types of Experimental
Design that investigate the
curvature of the response surface. They
achieve this by using a quadratic
regression
equation rather than the linear
form of the regression equation used in
factorial designs.
When the response surface is approximated
by a linear equation the maximum and minimum
values always occur at a corner point. Thus
it is not possible to use the regression
equation to optimize the process if the
true maximum or minimum lies within the
interior of the response surface.
There are various types of response surface
design including the Central
Composite (CCD) and
Box Behnken
designs.
