Social argument justification: Some mechanisms and conditions for their coincidence

Abstract

In this paper we analyze the problem of aggregating different individual argumentation frameworks over a common set of arguments in order to obtain a unique socially justified set of arguments. This can be done in two different ways: a social attack relation is built up from the individual ones, and then is used to produce a set of justified arguments, or this set is directly obtained from the sets of individually justified arguments. Our main concern here is whether these two procedures can coincide or under what conditions this could happen. To deal with this, we consider different voting by quota mechanisms, and the aggregation mechanisms by decisive sets. © 2009 Springer Berlin Heidelberg.