Generalized wordlength patterns and strength
arXiv:1207.1934 · doi:10.1016/j.jspi.2012.06.015
Abstract
Xu and Wu (2001) defined the \emph{generalized wordlength pattern} of an arbitrary fractional factorial design (or orthogonal array) on factors. They gave a coding-theoretic proof of the property that the design has strength if and only if . The quantities are defined in terms of characters of cyclic groups, and so one might seek a direct character-theoretic proof of this result. We give such a proof, in which the specific group structure (such as cyclicity) plays essentially no role. Nonabelian groups can be used if the counting function of the design satisfies one assumption, as illustrated by a couple of examples.