Linsbichler, Thomas
Design and Results of the Second International Competition on Computational Models of Argumentation
Gaggl, Sarah A., Linsbichler, Thomas, Maratea, Marco, Woltran, Stefan
Within AI, several sub-fields are particularly relevant to - and benefit from - studies of argumentation. These include decision support, knowledge representation, nonmonotonic reasoning, and multiagent systems. Moreover, computational argumentation provides a formal investigation of problems that have been studied informally only by philosophers, and which consequently allow for the development of computational tools for argumentation, see (Atkinson et al., 2017). Since its invention by Dung (1995), abstract argumentation based on argumentation frameworks (AFs) has become a key concept for the field. In AFs, argumentation scenarios are modeled as simple directed graphs, where the vertices represent arguments and each edge corresponds to an attack between two arguments. Besides its simplicity, there are several reasons for the success story of this concept: First, a multitude of semantics (Baroni et al., 2011, 2018) allows for tight coupling of argumentation with existing formalisms from the areas of knowledge representation and logic programming; indeed, one of the main motivations of Dung's work (Dung, 1995) was to give a uniform representation of several nonmonotonic formalisms including Reiter's Default Logic, Pollock's Defeasible Logic, and Logic Programming (LP) with default negation; the latter lead to a series of works that investigated the relationship between different LP semantics and different AF semantics, see e.g.
Summary Report of the Second International Competition on Computational Models of Argumentation
Gaggl, Sara A. (TU Dresden) | Linsbichler, Thomas (TU Wien) | Maratea, Marco (University of Genoa) | Woltran, Stefan (Vienna University of Technology)
One of NIST's research areas has been the quantification of Each team's system is faced with challenges such as The goal of ARIAC is to solidify the shown in figure 1. The organizers chose kitting field of robot agility, while also progressing the state because of its similarity to assembly. Teams were tasked with assembling a robotic system's (robot, controller, and sensors) ability kit both from bins of stationary parts and from a to respond to a dynamic environment. After the robotic system finished dynamic response includes handling errors like the kit, the kit was placed on an autonomous guided dropped parts or responding to changes in orders, all vehicle (AGV) and taken away. Teams were faced with such challenges as forced The competition addresses the aspect of robot dropped parts and in-process order changes.
Solving Advanced Argumentation Problems with Answer-Set Programming
Brewka, Gerhard (Universität Leipzig) | Diller, Martin (Technische Universität Wien) | Heissenberger, Georg (Technische Universität Wien) | Linsbichler, Thomas (Technische Universität Wien) | Woltran, Stefan (Technische Universität Wien)
Powerful formalisms for abstract argumentation have been proposed. Their complexity is often located beyond NP and ranges up to the third level of the polynomial hierarchy. The combined complexity of Answer-Set Programming (ASP) exactly matches this complexity when programs are restricted to predicates of bounded arity. In this paper, we exploit this coincidence and present novel efficient translations from abstract dialectical frameworks (ADFs) and GRAPPA to ASP.We also empirically compare our approach to other systems for ADF reasoning and report promising results.
An Extension-Based Approach to Belief Revision in Abstract Argumentation
Diller, Martin (Vienna University of Technology) | Haret, Adrian (Vienna University of Technology) | Linsbichler, Thomas (Vienna University of Technology) | Rümmele, Stefan (Vienna University of Technology) | Woltran, Stefan (Vienna University of Technology)
Argumentation is an inherently dynamic process. Given that argumentation can be viewed as a process as well Consequently, recent years have witnessed tremendous as a product, recent years have seen an increasing number of research efforts towards an understanding of studies on different problems in the dynamics of argumentation how the seminal AGM theory of belief change can frameworks [Baumann, 2012; Bisquert et al., 2011; 2013; be applied to argumentation, in particular for Dung's Boella et al., 2009; Booth et al., 2013; Cayrol et al., 2010; abstract argumentation frameworks (AFs). However, Doutre et al., 2014; Kontarinis et al., 2013; Krümpelmann et none of the attempts has yet succeeded in handling al., 2012; Nouioua and Würbel, 2014; Sakama, 2014]. The the natural situation where the revision of an AF is problem we tackle here is how to revise an AF when some new guaranteed to be representable by an AF as well.
Characteristics of Multiple Viewpoints in Abstract Argumentation
Dunne, Paul E. (University of Liverpool) | Dvorak, Wolfgang (University of Vienna) | Linsbichler, Thomas (Vienna University of Technology) | Woltran, Stefan (Vienna University of Technology)
The study of extension-based semantics within the seminal abstract argumentation model of Dung has largely focused on definitional, algorithmic and complexity issues. In contrast, matters relating to comparisons of representational limits, in particular, the extent to which given collections of extensions are expressible within the formalism, have been under-developed. As such, little is known concerning conditions under which a candidate set of subsets of arguments are “realistic” in the sense that they correspond to the extensions of some argumentation framework AF for a semantics of interest. In this paper we present a formal basis for examining extension-based semantics in terms of the sets of extensions that these may express within a single AF. We provide a number of characterization theorems which guarantee the existence of AFs whose set of extensions satisfy specific conditions and derive preliminary complexity results for decision problems that require such characterizations.