Empirical Evaluation of Abstract Argumentation: Supporting the Need for Bipolar and Probabilistic Approaches

In dialogical argumentation it is often assumed that the involved parties always correctly identify the intended statements posited by each other, realize all of the associated relations, conform to the three acceptability states (accepted, rejected, undecided), adjust their views when new and correct information comes in, and that a framework handling only attack relations is sufficient to represent their opinions. Although it is natural to make these assumptions as a starting point for further research, removing them or even acknowledging that such removal should happen is more challenging for some of these concepts than for others. Probabilistic argumentation is one of the approaches that can be harnessed for more accurate user modelling. The epistemic approach allows us to represent how much a given argument is believed by a given person, offering us the possibility to express more than just three agreement states. It is equipped with a wide range of postulates, including those that do not make any restrictions concerning how initial arguments should be viewed, thus potentially being more adequate for handling beliefs of the people that have not fully disclosed their opinions in comparison to Dung's semantics. The constellation approach can be used to represent the views of different people concerning the structure of the framework we are dealing with, including cases in which not all relations are acknowledged or when they are seen differently than intended. Finally, bipolar argumentation frameworks can be used to express both positive and negative relations between arguments. In this paper we describe the results of an experiment in which participants judged dialogues in terms of agreement and structure. We compare our findings with the aforementioned assumptions as well as with the constellation and epistemic approaches to probabilistic argumentation and bipolar argumentation

Merging Argumentation Systems

International audienc

P.: Merging argumentation systems

In this paper, we address the problem of deriving sensible information from a collection of argumentation systems coming from different agents. A general framework for merging argumentation systems from Dung’s theory of argumentation is presented. Each argumentation system gives both a set of arguments and the way they interact (i.e. attack or non-attack) according to the corresponding agent. The aim is to define the argument system (or the set of argument systems) that best represents the group. Our framework is general enough to handle the case when agents do not share the same set of arguments. Merging argumentation systems is shown as a valuable approach for defining (sets of) arguments acceptable by the group

Weighted Argumentation Systems: A Tool for Merging Argumentation Systems

International audienc

Merging argumentation systems with weighted argumentation systems: a preliminary study

International audienceIn this paper, we address the problem of merging argumentation systems in a multi-agent setting. Previous work [6] has proposed a two-step merging process in which conflicts about an interaction result in a new kind of interaction, called ignorance. However, this merging process is computationally expensive, and does not provide a single resulting argumentation system. We propose a novel approach to overcome these limitations by using a weighted argumentation system

On the Merging of Dung’s Argumentation Systems Sylvie Coste-Marquis a, Caroline Devred a,

In this paper, the problem of deriving sensible information from a collection of argumentation systems coming from different agents is addressed. The underlying argumentation theory is Dung’s one: each argumentation system gives both a set of arguments and the way they interact (i.e., attack or non-attack) according to the corresponding agent. The inadequacy of the simple, yet appealing, method which consists in voting on the agents ’ selected extensions calls for a new approach. To this purpose, a general framework for merging argumentation systems from Dung’s theory of argumentation is presented. The objective is achieved through a threestep process: first, each argumentation system is expanded into a partial system over the set of all arguments considered by the group of agents (reflecting that some agents may easily ignore arguments pointed out by other agents, as well as how such arguments interact with her own ones); then, merging is used on the expanded systems as a way to solve the possible conflicts between them, and a set of argumentation systems which are as close as possible to the whole profile is generated; finally, voting is used on the selected extensions of the resulting systems so as to characterize the acceptable arguments at the group level. Key words: Argumentation frameworks, Argument in agent system