A recently introduced
dualization technique for binary linear programs with equality
constraints, essentially due to Poljak et al. ,
and further developed in Lemaréchal and Oustry , leads
to simple alternative derivations of well-known, important
two well-known problems of discrete optimization: the
maximum stable set problem and the maximum vertex cover problem.
The resulting relaxation is easily transformed
to the well-known Lovász θ number.