In this paper, we define a labelling-based justification status of the arguments in an argumentation framework. Our proposal allows for a more fine-grained notion of a justification status than the traditional extensions-based approaches. In particular, we are able to distinguish different levels at which an argument can be accepted or rejected. Our approach is fully compatible with traditional...

In this paper we present an abstract argumentation framework for the support of agreement processes in agent societies. This framework takes into account arguments, attacks between them and the social contex of the agents that put forward arguments. Then, we define the semantics of the framework, providing a mechanism to evaluate arguments in view of other arguments posed in the argumentation p...

In this paper we propose an argumentative agent model able to reason and make decisions, communicate and negotiate with other agents with the aim of supporting service selection and composition. Actually, our agent model is inspired from the general-purpose KGP agent model which deals only partially with priorities as required by our application. We provide here an argumentation framework which...

Argumentation is a dialectical process of knowing things (inquiry) and justifying them (advocacy) in general. Computational argumentation has been recognized as a social computing mechanism or paradigm in the multi-agent systems community. We have developed a computational argumentation framework that basically consists of EALP (Extended Annotated Logic Programming) and LMA (Logic of Multipleva...

Argumentation is an essential skill in many aspects of life in private as well as in business. Nevertheless, many people struggle to engage in reasonable argumentation. Classic teaching methods fail to promote argumentation skills and, hence, independent knowledge acquisition by means of argumentation. An approach to deal with this issue is the use of computer tools to scaffold the education of...

Argumentation Scheme Frameworks Katie Atkinson and Trevor Bench-Capon Department of Computer Science University of Liverpool Liverpool L69 3BX UK {K.M.Atkinson,tbc}@liverpool.ac.uk Abstract. This paper presents an approach to modelling and reasoning about arguments that exploits and combines two of the most popular mechanisms used within computational modelling of argumentation: argumentation s...

This paper presents a novel approach to question answering: the use of argumentation techniques. Our question answering system deals with argumentation in student essays: it sees an essay as an answer to a question and gauges its quality on the basis of the argumentation found in it. Thus, the system looks for expected types of argumentation in essays (i.e. the expectation is that the kind of a...

The main purpose of argumentation theory is to study the fundamental mechanisms that humans use in argumentation, and to explore ways to implement these mechanisms on computers. During the last years, argumentation has been gaining increasing importance in Computer Science, especially in areas as Artificial Intelligence, e-commerce, Multi-agent Systems and Decision-Making. In this paper, we pre...

In this paper, we describe an open problem in abstract argumentation theory: the precise conditions under which semi-stable extensions exist. Although each finite argumentation framework can be shown to have at least one semi-stable extension, this is no longer the case when infinite argumentation frameworks are considered. This puts semi-stable semantics between stable and preferred semantics....