1,115 research outputs found
Modeling time and valuation in structured argumentation frameworks
Temporal Argumentation Frameworks (TAF) represent a recent extension of Dung's abstract argumentation frameworks that consider the temporal availability of arguments. In a TAF, arguments are valid during specific time intervals, called availability intervals, while the attack relation of the framework remains static and permanent in time; thus, in general, when identifying the set of acceptable arguments, the outcome associated with a TAF will vary in time. We introduce an extension of TAF, called Extended Temporal Argumentation Framework (E-TAF), adding the capability of modeling the temporal availability of attacks among arguments, thus modeling special features of arguments varying over time and the possibility that attacks are only available in a given time interval. E-TAF will be enriched by considering Structured Abstract Argumentation, using Dynamic Argumentation Frameworks. The resulting framework, E-TAF∗, provides a suitable model for different time-dependent issues satisfying properties and equivalence results that permit to contrast the expressivity of E-TAF and E-TAF∗ with argumentation based on abstract frameworks. Thus, the main contribution here is to provide an enhanced framework for modeling special features of argumentation varying over time, which are relevant in many real-world situations. The proposal aims at advancing in the integration of time and valuation in the context of argumentation systems as well.Fil: Budan, Maximiliano Celmo David. Universidad Nacional del Sur. Departamento de Ciencias e IngenierÃa de la Computación; Argentina. Universidad Nacional de Santiago del Estero. Facultad de Ciencias Exactas y TecnologÃas. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca; ArgentinaFil: Gomez Lucero, Mauro Javier. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca; Argentina. Universidad Nacional del Sur. Departamento de Ciencias e IngenierÃa de la Computación; ArgentinaFil: Chesñevar, Carlos Iván. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca; Argentina. Universidad Nacional de Santiago del Estero. Facultad de Ciencias Exactas y TecnologÃas. Departamento de Matemática; Argentina. Universidad Nacional del Sur. Departamento de Ciencias e IngenierÃa de la Computación; ArgentinaFil: Simari, Guillermo Ricardo. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca; Argentina. Universidad Nacional del Sur. Departamento de Ciencias e IngenierÃa de la Computación; Argentin
An Interleaving Semantics of the Timed Concurrent Language for Argumentation to Model Debates and Dialogue Games
Time is a crucial factor in modelling dynamic behaviours of intelligent
agents: activities have a determined temporal duration in a real-world
environment, and previous actions influence agents' behaviour. In this paper,
we propose a language for modelling concurrent interaction between agents that
also allows the specification of temporal intervals in which particular actions
occur. Such a language exploits a timed version of Abstract Argumentation
Frameworks to realise a shared memory used by the agents to communicate and
reason on the acceptability of their beliefs with respect to a given time
interval. An interleaving model on a single processor is used for basic
computation steps, with maximum parallelism for time elapsing. Following this
approach, only one of the enabled agents is executed at each moment. To
demonstrate the capabilities of language, we also show how it can be used to
model interactions such as debates and dialogue games taking place between
intelligent agents. Lastly, we present an implementation of the language that
can be accessed via a web interface. Under consideration in Theory and Practice
of Logic Programming (TPLP).Comment: Under consideration in Theory and Practice of Logic Programming
(TPLP
Preprocessing Argumentation Frameworks via Replacement Patterns
A fast-growing research direction in the study of formal argumentation is the development of practical systems for central reasoning problems underlying argumentation. In particular, numerous systems for abstract argumentation frameworks (AF solvers) are available today, covering several argumentation semantics and reasoning tasks. Instead of proposing another algorithmic approach for AF solving, we introduce in this paper distinct AF preprocessing techniques as a solver-independent approach to obtaining performance improvements of AF solvers. We establish a formal framework of replacement patterns to perform local simplifications that are faithful with respect to standard semantics for AFs. Moreover, we provide a collection of concrete replacement patterns. Towards potential applicability, we employ the patterns in a preliminary empirical evaluation of their influence on AF solver performance.Peer reviewe
On semantics in dynamic argumentation frameworks
A Timed Abstract Argumentation Framework is a novel formalism where arguments are only valid for consideration in a given period of time, which is defined for every individual argument. Thus, the attainability of attacks and defenses is related to time, and the outcome of the framework may vary accordingly. In this work we study the notion of stable extensions applied to timed-arguments. The framework is extended to include intermittent arguments, which are available with some repeated interruptions in time.XIV Workshop agentes y sistemas inteligentes.Red de Universidades con Carreras en Informática (RedUNCI
A Concurrent Language for Argumentation: Preliminary Notes
While agent-based modelling languages naturally implement concurrency, the currently available languages for argumentation do not allow to explicitly model this type of interaction. In this paper we introduce a concurrent language for handling process arguing and communicating using a shared argumentation framework (reminding shared constraint store as in concurrent constraint). We introduce also basic expansions, contraction and revision procedures as main bricks for enforcement, debate, negotiation and persuasion
On the combination of argumentation solvers into parallel portfolios
In the light of the increasing interest in efficient algorithms for solving abstract argumentation problems and the pervasive availability of multicore machines, a natural research issue is to combine existing argumentation solvers into parallel portfolios. In this work, we introduce six methodologies for the automatic configuration of parallel portfolios of argumentation solvers for enumerating the preferred extensions of a given framework. In particular, four methodologies aim at combining solvers in static portfolios, while two methodologies are designed for the dynamic configuration of parallel portfolios. Our empirical results demonstrate that the configuration of parallel portfolios is a fruitful way for exploiting multicore machines, and that the presented approaches outperform the state of the art of parallel argumentation solvers
An Efficient Java-Based Solver for Abstract Argumentation Frameworks: jArgSemSAT
Dung’s argumentation frameworks are adopted in a variety of applications, from
argument-mining, to intelligence analysis and legal reasoning. Despite this broad spectrum
of already existing applications, the mostly adopted solver—in virtue of its
simplicity—is far from being comparable to the current state-of-the-art solvers. On the
other hand, most of the current state-of-the-art solvers are far too complicated to be
deployed in real-world settings. In this paper we provide and extensive description of
jArgSemSAT, a Java re-implementation of ArgSemSAT. ArgSemSAT represents the best
single solver for argumentation semantics with the highest level of computational complexity.
We show that jArgSemSAT can be easily integrated in existing argumentation
systems (1) as an off-the-shelf, standalone, library; (2) as a Tweety compatible library;
and (3) as a fast and robust web service freely available on the Web. Our large experimental
analysis shows that—despite being written in Java—jArgSemSAT would have
scored in most of the cases among the three bests solvers for the two semantics with
highest computational complexity—Stable and Preferred—in the last competition on
computational models of argumentation
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