Weiwei Chen: Aggregation of Argumentative Stances
Channel: International Center for Formal Ontology
Date: 2018-11-26

3rd Summer School on Argumentation: Computational and Linguistic Perspectives (http://ssa2018.argdiap.pl/), 6th - 10th September 2018, Warsaw University of Technology, Poland.

Recording of student session. 
Weiwei Chen is a third-year Ph.D. student at Institute of Logic and Cognition and Department of Philosophy Sun Yat-sen University, China. 

When several agents are engaged in a debate, we may wish to aggregate their stances into a global view which represents the consensus of the group. Abstract argumentation [5] provides tools for modelling stances of agents at different levels of abstraction. An abstract argumentation framework is a set of arguments together with a binary attack-relation defined on this set. By indicating for every pair of arguments that is being considered in a debate whether the first attacks the second, an abstract argumentation framework can be used to model an agent’s argumentative stance. By identifying for every argument whether it is acceptable under the same abstract argumentation framework, an agent’s stance can be represented by a set of arguments. Similar question has received attention from authors in the past decade or so (see, e.g., [1, 4, 8, 9]). In my thesis, I investigate the problem of aggregation of argumentative stances at two levels. At the first level, I analyse in what circumstance the semantic properties agreed by the individuals will be preserved under aggregation. At this level, we make use of recent results in graph aggregation [6]. At the second level, I analyse the scenario of extension aggregation, i.e., a group of agents who each take an individual view on the merits of an extension, and we aggregate such extensions. At this level, we make use of known results in judgment aggregation [7]. At both levels, we are interested in the aggregation of individual points of view in the context of abstract argumentation. Even though the techniques are different, the preservation results are similar. At both levels, some properties are easy to preserve, such as conflict-freeness. Enforcing the preservation of some properties leads to rules that are unacceptable from an axiomatic point of view. This indicates that these properties are too demanding and relaxing the requirements of preservation is necessary.

Organizers of 3rd SSA:
- International Center for Formal Ontology, Faculty of Administration and Social Sciences, Warsaw University of Technology (http://icfo.ans.pw.edu.pl/),
- Bialystok University of Technology (http://pb.edu.pl/en/),
- Institute of Philosophy, University of Warsaw (http://www.philosophy.uw.edu.pl/?page_id=74),
- Institute of Informatics, University of Warsaw (https://www.mimuw.edu.pl/),
- Graduate School for Social Research (GSSR), Institute of Philosophy and Sociology, Polish Academy of Sciences (http://www.gssr.edu.pl/),
- ArgDiaP (http://argdiap.pl/).