On invariance and randomization under factor permutation in fractional factorial designs (Q793481)

This paper establishes the invariance of the spectrum of the information matrix under any subgroup \(\Gamma\) of the group \(\Delta\) of factor permutations relative to a \(\Gamma\)-closed subvector P. The authors have given a number of theorems and corollaries with regard to factor permutations \(\delta\) in a factor permutation group \(\Gamma\) and unbiased estimation of a linear function of a \(\Gamma\)-closed vector in the factorial setting. The applications of their work have been exemplified for the minimal d-optimal resolution III design of the \(2^ 3\) factorial.