Finding partitions of arguments with Dung's properties via SCSPs

Forming coalition structures allows agents to join their forces with the aim to achieve a common task. We suggest it would be interesting to look for homogeneous groups which follow distinct lines of thought. For this reason, we extend the Dung Argumentation Framework in order to deal with coalitions of arguments. The initial set of arguments is partitioned into subsets (or coalitions). Each coalition represents a different line of thought, but all the found coalitions show the same property inherited by Dung, e.g. all the coalitions in the partition are admissible (or conflict-free, complete, stable). Some problems in weighted argumentation are NP complete; we use (soft) constraints as a formal approach to reason about coalitions and to model all these problems in the same framework. Semiring algebraic structures can be used to model different optimization criteria for the obtained coalitions. To implement this mapping and practically find its solutions we use JaCoP, a Java constraint solver, and we test the code over a small-world network.