Binarisation for Valued Constraint Satisfaction Problems
  We study methods for transforming valued constraint satisfaction problems (VCSPs) to binary VCSPs. First, we show that the standard dual encoding preserves many aspects of the algebraic properties that capture the computational complexity of VCSPs. Second, we extend the reduction of CSPs to binary CSPs described by Bulin et al. [LMCS'15] to VCSPs. This reduction establishes that VCSPs over a fixed valued constraint language are polynomial-time equivalent to Minimum-Cost Homomorphism Problems over a fixed digraph. 
David A. Cohen and Martin C. Cooper and Peter G. Jeavons and Andrei   Krokhin and Robert Powell and Stanislav Zivny
cs.DM cs.CC