United we stand: Accruals in strength-based argumentation

Abstract

Argumentation has been an important topic in knowledge representation, reasoning and multi-agent systems during the last twenty years. In this paper, we propose a new abstract framework where arguments are associated with a strength, namely a quantitative information which is used to determine whether an attack between arguments succeeds or not. Our Strength-based Argumentation Framework (StrAF) combines ideas of Preference-based and Weighted Argumentation Frameworks in an original way, which permits to define acceptability semantics sensitive to the existence of accruals between arguments. The question of accruals arises in situations where several arguments defending the same position (but from different points of view) against another argument are unable to individually defeat this argument, but could do it collectively if they combine their strengths. We investigate some of the theoretical and computational properties of our new framework and semantics, and present a reasoning algorithm that is based on a translation of the problem into pseudo-boolean constraint satisfaction. This paper proposes an intuitive framework which allows strength compensations in an argumentation context where attacks may not succeed, completed by an approach which detects accruals throughout the reasoning process without requiring the elicitation of all compensatory combinations of arguments as an input.

Yes, no, maybe, I don’t know: Complexity and application of abstract argumentation with incomplete knowledge

“…how to add (uncertain) supports [3,30] to IAFs. This may also lead to an interesting combination of IAFs (or CAFs) with various frameworks like Weighted AFs [46], Strength-based AFs [76], Value-based AFs [20] or AFs with collective attacks (SETAFs) [71]. The question would then be to determine which arguments are acceptable when the agent is not sure about the weight of some attacks, the strength or the value of some arguments, or the existence of some sub-attack in a collective attack.…”

Stability in Abstract Argumentation

“…We are also interested in stability for other abstract argumentation frameworks. Besides preference-based argumentation that we have already mentioned, Dung's AFs has been generalized by adding a support relation (Amgoud et al 2008), or associating quantitative weights with attacks (Dunne et al 2011) or arguments (Rossit et al 2020), or associating values with arguments (Bench-Capon 2002). But adapting the notion of stability to these frameworks may require different techniques than the one used in this paper.…”

Preface for the special issue on argument strength

“…A new framework for representing the strength of arguments called Strength-based Argumentation Framework (StrAF) is proposed by Rossit et al [4]. Their proposal is based on Dung-style abstract argumentation, by associating an integer weight to each argument, that can also combine their attacking strengths (accrual) and allow comparison of the arguments' respective strengths.…”