# Complete Distributed Search Algorithm for Cyclic Factor Graphs

### Toshihiro Matsui, Hiroshi Matsuo

#### Abstract

Distributed Constraint Optimization Problems (DCOPs) have been studied as fundamental problems in multiagent systems. The Max-Sum algorithm has been proposed as a solution method for DCOPs. The algorithm is based on factor graphs that consist of two types of nodes for variables and functions. While the Max-Sum is an exact method for acyclic factor-graphs, in the case that the factor graph contains cycles, it is an inexact method that may not converge. In this study, we propose a method that decomposes the cycles based on crossedged pseudo-trees on factor-graphs. We also present a basic scheme of distributed search algorithms that generalizes complete search algorithms on the constraint graphs and Max-Sum algorithm.

#### References

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#### Paper Citation

#### in Harvard Style

Matsui T. and Matsuo H. (2014). **Complete Distributed Search Algorithm for Cyclic Factor Graphs** . In *Proceedings of the 6th International Conference on Agents and Artificial Intelligence - Volume 2: ICAART,* ISBN 978-989-758-016-1, pages 184-192. DOI: 10.5220/0004824301840192

#### in Bibtex Style

@conference{icaart14,

author={Toshihiro Matsui and Hiroshi Matsuo},

title={Complete Distributed Search Algorithm for Cyclic Factor Graphs},

booktitle={Proceedings of the 6th International Conference on Agents and Artificial Intelligence - Volume 2: ICAART,},

year={2014},

pages={184-192},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0004824301840192},

isbn={978-989-758-016-1},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 6th International Conference on Agents and Artificial Intelligence - Volume 2: ICAART,

TI - Complete Distributed Search Algorithm for Cyclic Factor Graphs

SN - 978-989-758-016-1

AU - Matsui T.

AU - Matsuo H.

PY - 2014

SP - 184

EP - 192

DO - 10.5220/0004824301840192