References of "Villata, Serena"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailYes, we can! Mining Arguments in 50 Years of US Presidential Campaign Debates
Haddadan, Shohreh UL; Villata, Serena; Cabrio, Elena

Scientific Conference (2019, July)

Political debates offer a rare opportunity for citizens to compare the candidates’ positions on the most controversial topics of the campaign. Thus they represent a natural application scenario for ... [more ▼]

Political debates offer a rare opportunity for citizens to compare the candidates’ positions on the most controversial topics of the campaign. Thus they represent a natural application scenario for Argument Mining. As existing research lacks solid empirical investigation of the typology of argument components in political debates, we fill this gap by proposing an Argument Mining approach to political debates. We address this task in an empirical manner by annotating 39 political debates from the last 50 years of US presidential campaigns, creating a new corpus of 29k argument components, labeled as premises and claims. We then propose two tasks: (1) identifying the argumentative components in such debates, and (2) classifying them as premises and claims. We show that feature-rich SVM learners and Neural Network architectures outperform standard baselines in Argument Mining over such complex data. We release the new corpus USElecDeb60To16 and the accompanying software under free licenses to the research community. [less ▲]

Detailed reference viewed: 18 (0 UL)
Full Text
Peer Reviewed
See detailAnnotation of Argument Components in Political Debates Data
Haddadan, Shohreh UL; Cabrio, Elena; Villata, Serena

in Proceedings of the Workshop on Annotation in Digital Humanities (2018)

n this paper, we present the annotation guidelines we defined for annotating arguments in political debates. In our guidelines, we consider each argument as being composed of a claim and one or more ... [more ▼]

n this paper, we present the annotation guidelines we defined for annotating arguments in political debates. In our guidelines, we consider each argument as being composed of a claim and one or more premises. The annotation process has started with defining the guidelines for three annotators containing examples from the data, and continued as cyclic process of evaluation and revision on the annotation to resolve the ambiguities in the guidelines. In this paper, we briefly discuss the resulting annotated dataset and give some examples of the annotation scheme. The quality of the annotated dataset is assessed by computing inter-annotator agreement using Krippendorf’s α coefficient on a portion of the dataset. [less ▲]

Detailed reference viewed: 101 (16 UL)
Full Text
Peer Reviewed
See detailPrioritized norms in formal argumentation
Liao, Beishui; Oren, Nir; van der Torre, Leon UL et al

in Journal of Logic and Computation (2018)

To resolve conflicts amongst norms, various non-monotonic formalisms can be used to perform prioritized normative reasoning. Meanwhile, formal argumentation provides a way to represent non-monotonic ... [more ▼]

To resolve conflicts amongst norms, various non-monotonic formalisms can be used to perform prioritized normative reasoning. Meanwhile, formal argumentation provides a way to represent non-monotonic logics. In this paper we propose a representation of prioritized normative reasoning by argumentation. Using hierarchical abstract normative systems (HANS), we define three kinds of prioritized normative reasoning approaches called Greedy, Reduction and Optimization. Then, after formulating an argumentation theory for a HANS, we show that for a totally ordered HANS, Greedy and Reduction can be represented in argumentation by applying the weakest link and the last link principles, respectively, and Optimization can be represented by introducing additional defeats capturing the idea that for each argument that contains a norm not belonging to the maximal obeyable set then this argument should be rejected. [less ▲]

Detailed reference viewed: 53 (5 UL)
Full Text
Peer Reviewed
See detailPreference in Abstract Argumentation
Kaci, Souhila; van der Torre, Leon UL; Villata, Serena

in Computational Models of Argument (2018)

Consider an argument A that is attacked by an argument B, while A is preferred to B. Existing approaches will either ignore the attack or reverse it. In this paper we introduce a new reduction of ... [more ▼]

Consider an argument A that is attacked by an argument B, while A is preferred to B. Existing approaches will either ignore the attack or reverse it. In this paper we introduce a new reduction of preference and attack to defeat, based on the idea that in such a case, instead of ignoring the attack, the preference is ignored. We compare this new reduction with the two existing ones using a principle-based approach, for the four Dung semantics. The principle-based or axiomatic approach is a methodology to choose an argumentation semantics for a particular application, and to guide the search for new argumentation semantics. For this analysis, we also introduce a fourth reduction, and a semantics for preference-based argumentation based on extension selection. Our classification of twenty alternatives for preference-based abstract argumentation semantics using six principles suggests that our new reduction has some advantages over the existing ones, in the sense that if the set of preferences increases, the sets of accepted arguments increase as well. [less ▲]

Detailed reference viewed: 47 (6 UL)
Full Text
Peer Reviewed
See detailEthics by Design: Necessity or Curse?
Dignum, Virginia; Baldoni, Matteo; Baroglio, Cristina et al

in Proceedings of the 2018 AAAI/ACM Conference on AI, Ethics, and Society AIES 2018, New Orleans, LA, USA, February 02-03, 2018 (2018)

Ethics by Design concerns the methods, algorithms and tools needed to endow autonomous agents with the capability to reason about the ethical aspects of their decisions, and the methods, tools and ... [more ▼]

Ethics by Design concerns the methods, algorithms and tools needed to endow autonomous agents with the capability to reason about the ethical aspects of their decisions, and the methods, tools and formalisms to guarantee that an agent's behavior remains within given moral bounds. In this context some questions arise: How and to what extent can agents understand the social reality in which they operate, and the other intelligences (AI, animals and humans) with which they co-exist? What are the ethical concerns in the emerging new forms of society, and how do we ensure the human dimension is upheld in interactions and decisions by autonomous agents?. But overall, the central question is: "Can we, and should we, build ethically-aware agents?" This paper presents initial conclusions from the thematic day of the same name held at PRIMA2017, on October 2017. [less ▲]

Detailed reference viewed: 54 (0 UL)
Full Text
Peer Reviewed
See detailPrioritized Norms in Formal Argumentation
Liao, Beishui UL; Oren, Nir; van der Torre, Leon UL et al

in Journal of Logic & Computation (2017), abs/1709.08034

To resolve conflicts among norms,various nonmonotonic formalisms can be used to perform prioritized normative reasoning. Meanwhile, formal argumentation provides a way to represent nonmonotonic logics. In ... [more ▼]

To resolve conflicts among norms,various nonmonotonic formalisms can be used to perform prioritized normative reasoning. Meanwhile, formal argumentation provides a way to represent nonmonotonic logics. In this paper, we propose a representation of prioritized normative reasoning by argumentation. Using hierarchical abstract normative systems, we define three kinds of prioritized normative reasoning approaches, called Greedy, Reduction, and Optimization. Then, after formulating an argumentation theory for a hierarchical abstract normative system, we show that for a totally ordered hierarchical abstract normative system, Greedy and Reduction can be represented in argumentation by applying the weakest link and the last link principles respectively, and Optimization can be represented by introducing additional defeats capturing implicit conflicts between arguments. [less ▲]

Detailed reference viewed: 63 (5 UL)
Full Text
Peer Reviewed
See detailHandling Norms in Multi-Agent System by Means of Formal Argumentation
Peirera, Célia da Costa; Tettamanzi, Andrea G. B.; Villata, Serena et al

in IfCoLog Journal of Logics and Their Applications (2017)

Formal argumentation is used to enrich and analyse normative multi-agent systems in various ways. In this chapter, we discuss three examples from the literature of handling norms by means of formal ... [more ▼]

Formal argumentation is used to enrich and analyse normative multi-agent systems in various ways. In this chapter, we discuss three examples from the literature of handling norms by means of formal argumentation. First, we discuss how existing ways to resolve conflicts among norms using priorities can be represented in formal argumentation, by showing that the so-called Greedy and Reduction approaches can be represented using the weakest and the last link principles respectively. Based on such representation results, formal argumentation can be used to explain the detachment of obligations and permissions from hierarchical normative systems in a new way. Second, we discuss how formal argumentation can be used as a general theory for developing new approaches for normative reasoning, using a dynamic ASPIC-based legal argumentation theory. We show how existing logics of normative systems can be used to analyse such new argumentation systems. Third, we show how argumentation can be used to reason about other challenges in the area of normative multiagent systems as well, by discussing a model for arguing about legal interpretation. In particular, we show how fuzzy logic combined with formal argumentation can be used to reason about the adoption of graded categories and thus address the problem of open texture in normative interpretation. Our aim to discuss these three examples is to inspire new applications of formal argumentation to the challenges of normative reasoning in multiagent systems. [less ▲]

Detailed reference viewed: 73 (15 UL)
Peer Reviewed
See detailPRIMA 2017: Principles and Practice of Multi-Agent Systems - 20th International Conference, Nice, France, October 30 - November 3, 2017 Proceedings
An, Bo; Bazzan, Ana L. C.; Leite, João et al

Scientific Conference (2017)

Detailed reference viewed: 56 (4 UL)
Full Text
Peer Reviewed
See detailPrioritized Norms and Defaults in Formal Argumentation
Liao, Beishui; Oren, Nir; van der Torre, Leon UL et al

in Deontic Logic and Normative Systems (2016) (2016)

Deontic logic sentences define what an agent ought to do when faced with a set of norms. These norms may come into conflict such that a priority ordering over them is necessary to resolve these conflicts ... [more ▼]

Deontic logic sentences define what an agent ought to do when faced with a set of norms. These norms may come into conflict such that a priority ordering over them is necessary to resolve these conflicts. Dung's seminal paper raised the - so far open - challenge of how to use formal argumentation to represent non monotonic logics, highlighting argumentation's value in exchanging, communicating and resolving possibly conflicting viewpoints in distributed scenarios. In this paper, we propose a formal framework to study various properties of prioritized non monotonic reasoning in formal argumentation, in line with this idea. More precisely, we show how a version of prioritized default logic and Brewka-Eiter's construction in answer set programming can be obtained in argumentation via the weakest and last link principles. We also show how to represent Hansen's recent construction for prioritized normative reasoning by adding arguments using weak contraposition via permissive norms, and their relationship to Caminada's "hang yourself" arguments. [less ▲]

Detailed reference viewed: 84 (10 UL)
Full Text
Peer Reviewed
See detailAn ASPIC-based legal argumentation framework for deontic reasoning
van der Torre, Leon UL; Villata, Serena

in Computational Models of Argument (2014)

In the last years, argumentation theory has been exploited to reason about norms, argue about enforced obligations and permissions, and establish the validity of norms seen as argumentative claims. In ... [more ▼]

In the last years, argumentation theory has been exploited to reason about norms, argue about enforced obligations and permissions, and establish the validity of norms seen as argumentative claims. In this paper, we start from the dynamic legal argumentation framework recently proposed by Prakken and Sartor, and we extend their ASPIC-based system by introducing deontic modalities, to include also normative concepts like factual and deontic detachment, and normative dynamics. Properties of the original and proposed legal argumentation system are presented and discussed, and related to deontic logic and logics of normative systems. [less ▲]

Detailed reference viewed: 50 (3 UL)
Full Text
Peer Reviewed
See detailSocial Interaction Based Audience Segregation for Online Social Networks.
van der Torre, Leon UL; Ahmed, Javed; Governatori, Guido et al

in Proceedings of the European Conference on Social Intelligence (2014)

Online social networking is the latest craze that has captured the attention of masses, people use these sites to communicate with their friends and family. These sites o er attractive means of social ... [more ▼]

Online social networking is the latest craze that has captured the attention of masses, people use these sites to communicate with their friends and family. These sites o er attractive means of social interac- tions and communications, but also raise privacy concerns. This paper examines user's abilities to control access to their personal information posted in online social networks. Online social networks lack common mechanism used by individuals in their real life to manage their privacy. The lack of such mechanism signi cantly a ects the level of user control over their self presentation in online social networks. In this paper, we present social interaction based audience segregation model for online so- cial networks. This model mimics real life interaction patterns and makes online social networks more privacy friendly. Our model uses type, fre- quency, and initiation factor of social interactions to calculate friendship strength. The main contribution of the model is that it considers set of all possible interactions among friends and assigns a numerical weight to each type of interaction in order to increase or decrease its contribu- tion in calculation of friendship strength based on its importance in the development of relationship ties. [less ▲]

Detailed reference viewed: 42 (4 UL)
Full Text
Peer Reviewed
See detailCombining Norms, Roles, Dependence and Argumentation in Agreement Technologies.
Caire, Patrice UL; van der Torre, Leon UL; Villata, Serena

in 25th Benelux Conference on Artificial Intelligence BNAIC'13. Delft, Nov. 7-8. (2013, November)

A major challenge for Agreement Technologies is the combination of existing technologies and rea- soning methods. In this paper we focus on the three core layers of the Agreement Technologies tower ... [more ▼]

A major challenge for Agreement Technologies is the combination of existing technologies and rea- soning methods. In this paper we focus on the three core layers of the Agreement Technologies tower, called Norms, Organization and Argumentation. We present a framework for arguing about agreements based on norms, roles and dependence, together with a case study from the sharing economy. [less ▲]

Detailed reference viewed: 62 (2 UL)
Full Text
Peer Reviewed
See detailCombining Norms, Roles, Dependence and Argumentation in Agreement Technologies
Caire, Patrice UL; van der Torre, Leon UL; Villata, Serena

in AAA' 13. International Workshop on Argument for Agreement and Assurance, Kanagawa, Japan, Oct. 27-28. (2013, October 27)

A major challenge for Agreement Technologies is the combination of existing technologies and rea- soning methods. In this paper we focus on the three core layers of the Agreement Technologies tower ... [more ▼]

A major challenge for Agreement Technologies is the combination of existing technologies and rea- soning methods. In this paper we focus on the three core layers of the Agreement Technologies tower, called Norms, Organization and Argumentation. We present a framework for arguing about agreements based on norms, roles and dependence, together with a case study from the sharing economy. [less ▲]

Detailed reference viewed: 44 (6 UL)
Full Text
Peer Reviewed
See detailArgumentation Theoretic Foundations for Abstract Dependence Networks
Caire, Patrice UL; van der Torre, Leon UL; Villata, Serena

in International Conference on Agreement Technologies, proceedings in Springer LNCS (2013)

In this paper we show how to argue about agreements based on de- pendence. First, we introduce a formal theory of arguing about agreements by instantiating Dung’s abstract theory of argumentation with ... [more ▼]

In this paper we show how to argue about agreements based on de- pendence. First, we introduce a formal theory of arguing about agreements by instantiating Dung’s abstract theory of argumentation with proposals for agree- ments represented as dependence networks. Second, we show that acceptable agreements are exchange based—satisfying the so-called do-ut-des principle— and not redundant. Third, to further decrease the number of proposals, we define a notion of minimal proposals. Roughly, all proposals can be split into a number of minimal sub-proposals such that if the proposal is acceptable, then its minimal sub-proposals are acceptable too. We show that minimal proposals satisfy the indecomposable do-ut-des property, i.e., they cannot be split into two nonempty sub-proposals with at most one shared agent. [less ▲]

Detailed reference viewed: 108 (7 UL)
Full Text
Peer Reviewed
See detailA socio-cognitive model of trust using argumentation theory
Villata, Serena; Boella, Guido; Gabbay, Dov M. UL et al

in Int. J. Approx. Reasoning (2013), 54(4), 541--559

Detailed reference viewed: 36 (3 UL)
Full Text
Peer Reviewed
See detailA logic of argumentation for specification and verification of abstract argumentation frameworks
Villata, Serena; Boella, Guido; Gabbay, Dov M. UL et al

in Annals of Mathematics & Artificial Intelligence (2012), 66(1-4), 199-230

In this paper, we propose a logic of argumentation for the specification and verification (LA4SV) of requirements on Dung’s abstract argumentation frameworks. We distinguish three kinds of decision ... [more ▼]

In this paper, we propose a logic of argumentation for the specification and verification (LA4SV) of requirements on Dung’s abstract argumentation frameworks. We distinguish three kinds of decision problems for argumentation verification, called extension verification, framework verification, and specification verification respectively. For example, given a political requirement like “if the argument to increase taxes is accepted, then the argument to increase services must be accepted too,” we can either verify an extension of acceptable arguments, or all extensions of an argumentation framework, or all extensions of all argumentation frameworks satisfying a framework specification. We introduce the logic of argumentation verification to specify such requirements, and we represent the three verification problems of argumentation as model checking and theorem proving properties of the logic. Moreover, we recast the logic of argumentation verification in a modal framework, in order to express multiple extensions, and properties like transitivity and reflexivity of the attack relation. Finally, we introduce a logic of meta-argumentation where abstract argumentation is used to reason about abstract argumentation itself. We define the logic of meta-argumentation using the fibring methodology in such a way to represent attack relations not only among arguments but also among attacks. [less ▲]

Detailed reference viewed: 78 (5 UL)
Full Text
Peer Reviewed
See detailOn Input/Output Argumentation Frameworks
Baroni, Pietro UL; Boella, Guido UL; Cerutti, Federico et al

in Proceedings of COMMA (2012)

This paper introduces Input/Output Argumentation Frameworks, a novel approach to characterize the behavior of an argumentation framework as a sort of black box exposing a well-defined external interface ... [more ▼]

This paper introduces Input/Output Argumentation Frameworks, a novel approach to characterize the behavior of an argumentation framework as a sort of black box exposing a well-defined external interface. As a starting point, we define the novel notion of semantics decomposability and analyze complete, stable, grounded and preferred semantics in this respect. Then we show as a main result that, under grounded, complete, stable and credulous preferred semantics, Input/Output Argumentation Frameworks with the same behavior can be interchanged without affecting the result of semantics evaluation of other arguments interacting with them [less ▲]

Detailed reference viewed: 35 (3 UL)
Full Text
Peer Reviewed
See detailModelling defeasible and prioritized support in bipolar argumentation
Villata, Serena; Boella, Guido; Gabbay, Dov M. UL et al

in Annals of Mathematics & Artificial Intelligence (2012), 66(1-4), 163-197

Cayrol and Lagasquie-Schiex introduce bipolar argumentation frameworks by introducing a second relation on the arguments for representing the support among them. The main drawback of their approach is ... [more ▼]

Cayrol and Lagasquie-Schiex introduce bipolar argumentation frameworks by introducing a second relation on the arguments for representing the support among them. The main drawback of their approach is that they cannot encode defeasible support, for instance they cannot model an attack towards a support relation. In this paper, we introduce a way to model defeasible support in bipolar argumentation frameworks. We use the methodology of meta-argumentation in which Dung’s theory is used to reason about itself. Dung’s well-known admissibility semantics can be used on this meta-argumentation framework to compute the acceptable arguments, and all properties of Dung’s classical theory are preserved. Moreover, we show how different contexts can lead to the alternative strengthening of the support relation over the attack relation, and converse. Finally, we present two applications of our methodology for modeling support, the case of arguments provided with an internal structure and the case of abstract dialectical frameworks. [less ▲]

Detailed reference viewed: 62 (4 UL)
Full Text
Peer Reviewed
See detailVisualizing Normative Systems: an Abstract Approach
Colombo Tosatto, Silvano UL; Boella, Guido; van der Torre, Leon UL et al

in Agotnes, Thomas; Broersen, Jan; Elgesem, Dag (Eds.) Deontic Logic in Computer Science - 11th International Conference, DEON 2012, Bergen, Norway, July 16-18, 2012. Proceedings (2012)

Abstract normative systems allow to reason with norms even when their content is not detailed. In this paper, we propose a our preliminary results to visualize abstract normative systems, in such a way ... [more ▼]

Abstract normative systems allow to reason with norms even when their content is not detailed. In this paper, we propose a our preliminary results to visualize abstract normative systems, in such a way that we are able to reason with institutional facts, obligations and permissions. Moreover, we detect meaningful patterns emerging from the proposed visualization, and we show how these patterns can be used to define commonly used reusable solutions. [less ▲]

Detailed reference viewed: 66 (4 UL)
Full Text
Peer Reviewed
See detailDependence Networks for Agreement Technologies
Boella, Guido; Caire, Patrice UL; van der Torre, Leon UL et al

in AT2012, Agreement Technologies, Proceedings of the First International Conference on Agreement Technologies (2012)

Detailed reference viewed: 59 (1 UL)