## Exploiting Problem Structure for Distributed Constraint Optimization (1995)

Venue: | In Proceedings of the First International Conference on Multi-Agent Systems |

Citations: | 42 - 2 self |

### BibTeX

@INPROCEEDINGS{Liu95exploitingproblem,

author = {Jyishane Liu and Katia P. Sycara},

title = {Exploiting Problem Structure for Distributed Constraint Optimization},

booktitle = {In Proceedings of the First International Conference on Multi-Agent Systems},

year = {1995},

pages = {246--253},

publisher = {MIT Press}

}

### OpenURL

### Abstract

Distributed constraint optimization imposes considerable complexity in agents' coordinated search for an optimal solution. However, in many application domains, problems often exhibit special structures that can be exploited to facilitate more efficient problem solving. One of the most recurrent structures involves disparity among subproblems. We present a coordination mechanism, Anchor&Ascend, for distributed constraint optimization that takes advantage of disparity among subproblems to efficiently guide distributed local search for global optimality. The coordination mechanism assigns different overlapping subproblems to agents who must interact and iteratively converge on a solution. In particular, an anchor agent who conducts local best first search to optimize its subsolution interacts with the rest of the agents who perform distributed constraint satisfaction to enforce problem constraints and constraints imposed by the anchor agent. We focus our study on the well-known NP-comple...

### Citations

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Citation Context ...ntiation) to all variables, such that all constraints are satisfied. Recent work in DAI has considered the distributed CSPs (DCSPs) (Huhns & Bridgeland 1991) (Sycara et al. 1991) (Yokoo et al. 1992) (=-=Liu & Sycara 1993-=-) in which variables of a CSP are distributed among agents. Each agent has a subset of variables and coordinates with other agents in instantiating its variables so that a global solution can be found... |

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Citation Context ...buted CSPs (DCSPs) the behavior of the Anchor&Ascend procedure under differ(Huhns & Bridgeland 1991) (Sycara et al. 1991) (Yokoo et ent conditions of subproblem disparity. Our experimental al. 1992) (=-=Liu & Sycara 1993-=-) in which variables of a CSP results show that Anchor&Ascend is most effective under are distributed among agents. Each agent has a subset of conditions of high disparity ratio and low disparity comp... |

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