A detailed description of the design of experiments theory can be found in Box
and Draper (1987), Myers and Montgomery (1995) and Montgomery (1997), among
many others. Schoofs (1987) has reviewed the application of experimental design to
structural optimization, Unal et al. (1996) discussed the use of several designs for
response surface methodology and multidisciplinary design optimization and
Simpson et al. (1997) presented a complete review of the use of statistics in design.
As introduced in Section 3.1, a particular combination of runs defines an
experimental design. The possible settings of each independent variable in the Ndimensional
space are called levels. A comparison of different methodologies is
given in the next section.