We introduce a derivative of Dung's seminal abstract argumentation frameworks (afs) through which distinctive features both of Dung's semantics and so-called “value-based” argumentation frameworks (vafs) may be captured. These frameworks, which we describe as uniform afs, thereby recognise that, in some circumstances, arguments may be deemed acceptable, not only as a consequence of subjective viewpoints (as are modelled by the concept of audience in vafs) but also as a consequence of “value independent” acceptance of other arguments: for example in the case of factual statements. We analyse divers acceptability conditions for arguments in uniform afs and obtain a complete picture for the computational complexity of the associated decision questions. Amongst other results it is shown that reasoning in uniform afs may pose significantly greater computational challenges than either standard or value-based questions, a number of problems being complete for the third level of the polynomial hierarchy.
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