New Weak Admissibility Semantics for Abstract Argumentation

Baumann, Brewka and Ulbricht recently introduced weak admissibility as an alternative to Dung’s notion of admissibility, and they used it to define weakly preferred, weakly complete and weakly grounded semantics of argumentation frameworks. In earlier work, we introduced two variants of their new semantics which we called qualified and semi-qualified semantics. We analysed all known variants of weak admissibility semantics with respect to some of the principles discussed in the literature on abstract argumentation, as well as some new principles we introduced to distinguish them all. Such a principle-based analysis can be used not only for selecting a semantics for an application, or for algorithmic design, but also for further research into weak admissibility semantics. In this paper, we introduce six new kinds of semantics based on weak admissibility, and we provide an initial principle-based analysis. The analysis illustrates various ways in which the new semantics improve on existing ones.