Characterizing change in abstract argumentation systems
Résumé
An argumentation system can undergo changes (ad-
dition/removal of arguments/interactions). At an abstract level, we
propose a typology to classify the different properties describing a
change operation. This typology reflects the evolution of three fea-
tures:
•the set of extensions in Dung’s sense (e.g., the set of extensions
is empty before the change and not empty after the change),
•the sets of accepted arguments (e.g., all the arguments skeptically
accepted before the change are still skeptically accepted after the
change) and
•the status of some given argument (e.g., an accepted argument
may become rejected after the change).
Then, an important issue is to provide characterizations for these
properties: i.e. conditions on the argumentation system and on the
change operation that are necessary or sufficient to guarantee that
the properties are satisfied.
So, in this paper, we present this typology and the characterization
results obtained either directly or by using an approach based on a
notion of duality. Our results are twofold, they can be considered
as a guide for selecting the change operation to perform in order to
obtain a desired property on an argumentation system and they may
also be used as a tool for predicting the result of a change operation
in a given context