Graph-Based Dispute Derivations in Assumption-Based Argumentation

Abstract. Arguments in structured argumentation are usually defined as trees. This introduces both conceptual redundancy and inefficiency in standard methods of implementation. We introduce rule-minimal ar-guments and argument graphs to solve these problems, studying their use in assumption-based argumentation (ABA), a well-known form of structured argumentation. In particular, we define a new notion of graph-based dispute derivations for determining acceptability of claims under the grounded semantics in ABA, study formal properties and present an experimental evaluation thereof.