Argumentation as distributed constraint satisfaction

Abstract

Conflict resolution is a critical problem in distributed and collaborative multi-agent systems. Negotiation via argumentation (NVA), where agents provide explicit arguments or justifications for their proposals for resolving conflicts, is an effective approach to resolve conflicts. Indeed, we are applying argumentation in some realworld multi-agent applications. However, a key problem in such applications is that a well-understood computational model of argumentation is currently missing, making it difficult to investigate convergence and scalability of argumentation techniques, and to understand and characterize different collaborative NVA strategies in a principled manner. To alleviate these difficulties, we present distributed constraint satisfaction problem (DCSP) as a computational model for investigating NVA. We model argumentation as constraint propagation in DCSP. This model enables us to study convergence properties of argumentation, and formulate and experimentally compare 16 different NVA strategies with different levels of agent cooperativeness towards others. One surprising result from our experiments is that maximizing cooperativeness is not necessarily the best strategy even in a completely cooperative environment. The paper illustrates the usefulness of these results in applying NVA to multi-agent systems, as well as to DCSP systems in general.

Integrative negotiation in complex organizational agent systems

“…Our experimental work has shown that even in a cooperative system it may not be the best for the social welfare to have agents be fully cooperative. Similar result is also shown in [4], which uses the distributed constraint satisfaction model that is much different from the underlying model in this work.…”

Building Coordinated Real-Time Control Plans

“…Other work on multi-agent team coordination has focussed on "joint intentions" and using explicit models of team plans to define individual agent plans (Tambe 1997), often using constraint satisfaction and on-line repairs to adapt to evolving environments and conflicts between agent plans (Jung, Tambe, & Kulkarni 2001;Tate, Levine, & Dalton 1999). While the higher levels of the CIRCA architecture do support elements of this approach, our current work is focused on building plans that accurately model and control the dynamics of coordination between agents at run-time.…”

A Decentralized Variable Ordering Method for Distributed Constraint Optimization

“…Sensor networks [4], distributed scheduling [5], military unmanned aerial vehicles teams [6] all are applications, where DCOP is or can be used to coordinate the decisions of autonomous agents.…”

“…Consider for example the collective choice of firing positions by unmanned helicopters, presented in [6]. The constraint graph for this task has a chain structure, with every agent sharing constraints with its left and right neighbors (Fig.…”

“…This requirement does not allow to apply ADOPT to domains in which information about the constraint graph cannot be gathered together and processed by a single unit. Sensor networks [6] is an example of such domain.…”