8,708 research outputs found
Preservation of Semantic Properties during the Aggregation of Abstract Argumentation Frameworks
An abstract argumentation framework can be used to model the argumentative
stance of an agent at a high level of abstraction, by indicating for every pair
of arguments that is being considered in a debate whether the first attacks the
second. When modelling a group of agents engaged in a debate, we may wish to
aggregate their individual argumentation frameworks to obtain a single such
framework that reflects the consensus of the group. Even when agents disagree
on many details, there may well be high-level agreement on important semantic
properties, such as the acceptability of a given argument. Using techniques
from social choice theory, we analyse under what circumstances such semantic
properties agreed upon by the individual agents can be preserved under
aggregation.Comment: In Proceedings TARK 2017, arXiv:1707.0825
Extending Modular Semantics for Bipolar Weighted Argumentation (Technical Report)
Weighted bipolar argumentation frameworks offer a tool for decision support
and social media analysis. Arguments are evaluated by an iterative procedure
that takes initial weights and attack and support relations into account. Until
recently, convergence of these iterative procedures was not very well
understood in cyclic graphs. Mossakowski and Neuhaus recently introduced a
unification of different approaches and proved first convergence and divergence
results. We build up on this work, simplify and generalize convergence results
and complement them with runtime guarantees. As it turns out, there is a
tradeoff between semantics' convergence guarantees and their ability to move
strength values away from the initial weights. We demonstrate that divergence
problems can be avoided without this tradeoff by continuizing semantics.
Semantically, we extend the framework with a Duality property that assures a
symmetric impact of attack and support relations. We also present a Java
implementation of modular semantics and explain the practical usefulness of the
theoretical ideas
Dealing with Qualitative and Quantitative Features in Legal Domains
In this work, we enrich a formalism for argumentation by including a formal
characterization of features related to the knowledge, in order to capture
proper reasoning in legal domains. We add meta-data information to the
arguments in the form of labels representing quantitative and qualitative data
about them. These labels are propagated through an argumentative graph
according to the relations of support, conflict, and aggregation between
arguments.Comment: arXiv admin note: text overlap with arXiv:1903.0186
A structured argumentation framework for detaching conditional obligations
We present a general formal argumentation system for dealing with the
detachment of conditional obligations. Given a set of facts, constraints, and
conditional obligations, we answer the question whether an unconditional
obligation is detachable by considering reasons for and against its detachment.
For the evaluation of arguments in favor of detaching obligations we use a
Dung-style argumentation-theoretical semantics. We illustrate the modularity of
the general framework by considering some extensions, and we compare the
framework to some related approaches from the literature.Comment: This is our submission to DEON 2016, including the technical appendi
Manipulation in Group Argument Evaluation.
Given an argumentation framework and a group of agents, the individuals may have divergent opinions on the status of the arguments. If the group needsto reach a common position on the argumentation framework, the question is how the individual evaluations can be mapped into a collective one. Thisproblem has been recently investigated by Caminada and Pigozzi. In this paper, we investigate the behaviour of two of such operators from a socialchoice-theoretic point of view. In particular, we study under which conditions these operators are Pareto optimal and whether they are manipulable.Social choice theory; Judgment aggregation; Argumentation; Collective decision making;
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