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S. Gaggl, S. Woltran:
"The cf2 argumentation semantics revisited.";
Journal of Logic and Computation, 23 (2013), 5; 925 - 949.

Numerous semantics for this paradigm have been proposed, whereby the cf2 semantics has shown to solve particular problems
concerned with odd-length cycles in such frameworks. Due to the complicated definition of this semantics it has somehow
been neglected in the literature. In this article, we introduce an alternative characterization of the cf2 semantics which, roughly
speaking, avoids the recursive computation of subframeworks. This facilitates further investigation steps, like a complete
complexity analysis. Furthermore, we show how the notion of strong equivalence can be characterized in terms of the cf2
semantics. In contrast to other semantics, it turns out that for the cf2 semantics strong equivalence coincides with syntactical
equivalence.We make this particular behaviour more explicit by defining a new property for argumentation semantics, called
the succinctness property. If a semantics σ satisfies the succinctness property, then for every framework F, all its attacks
contribute to the evaluation of at least one framework F containing F.We finally characterize strong equivalence also for the
stage and the naive semantics. Together with known results these characterizations imply that none of the prominent semantics
for abstract argumentation, except the cf2 semantics, satisfies the succinctness property.

http://dx.doi.org/10.1093/logcom/exs011