SOME RESULTS ON 2(N-K) FRACTIONAL FACTORIAL-DESIGNS AND SEARCH FOR MINIMUM ABERRATION DESIGNS

In this paper we find several interesting properties of 2n-k fractional factorial designs. An upper bound is given for the length of the longest word in the defining contrasts subgroup. We obtain minimum aberration 2n-k designs for k = 5 and any n. Furthermore, we give a method to test the equivalence of fractional factorial designs and prove that minimum aberration 2n-k designs for k less-than-or-equal-to 4 are unique.