Abstract
The paper proposes Maximum Residue (MR) as
a notion to evaluate the strength of a symmetry
breaking method. We give a proof to improve
the best known DoubleLex MR upper bound from
m!n! ! (m! + n!) to min(m!, n!) for an m × n
matrix model. Our result implies that DoubleLex
works well on matrix models where min(m, n) is
relatively small. We further study the MR bounds
of SwapNext and SwapAny, which are extensions
to DoubleLex breaking further a small number of
composition symmetries. Such theoretical comparisons suggest general principles on selecting Lexbased symmetry breaking methods based on the dimensions of the matrix models. Our experiments
confirm the theoretical predictions as well as effi-
ciency of these methods