Pseudocodewords from Bethe Permanents

Abstract

It was recently conjectured that a vector with components equal to the Bethe permanent of certain submatrices of a parity-check matrix is a pseudocodeword. In this paper we prove a stronger version of this conjecture for some important cases and investigate the families of pseudocodewords obtained by using the Bethe permanent. We also highlight some interesting properties of the permanent of block matrices and their effects on pseudocodewords.