@conference {4586, title = {Soft Global Constraints in Distributed Constraint Optimization}, booktitle = {AAMAS 2012 workshop: International Workshop on Optimisation in Multi-Agent Systems}, year = {2012}, month = {04/06/2012}, pages = {43{\textendash}50}, address = {Valencia, Spain}, abstract = {In the centralized context, global constraints have been essential for the advancement of constraint reasoning. In this paper we propose to include soft global constraints in distributed constraint optimization problems (DCOPs), using three representations: direct, binary and nested. We extend the distributed search algorithm BnB-ADOPT$^+$ to support these three representations of global constraints. In addition, we explore the relation of global constraints with soft local consistency in DCOPs, in particular for the generalized soft arc consistency (GAC) level. We include specific propagators for the \emph{soft-all-different} and the \emph{soft-at-most} constraint and measure their impact in the solving process, providing empirical results on several benchmarks.}, author = {Christian Bessi{\`e}re and Ismel Brito and Patricia Gutierrez and Pedro Meseguer} }