{'fraction_non_alphanumeric': 0.020205366015236835, 'fraction_numerical': 0.000662471016893011, 'mean_word_length': 5.550976138828633, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Between Argument and Conclusion - Argument-based Approaches to Discussion, Inference and Uncertainty

Formal argumentation has become a popular approach for nonmonotonic reasoning and multi-agent communication in Artificial Intelligence and Computer Science. The approach of Dung on the semantics of abstract argumentation frameworks, which specifies different criteria for selecting arguments given an argumentation framework, received a lot of followup. This work aims to enhance today’s generation of argumentation formalisms and make it become suitable for a wider variety of real-life applications. A number of dialectical proof procedures are associated with some argumentation semantics, e.g., grounded and preferred semantics. However, there were still some argumentation semantics, e.g., stable semantics that did not have associated dialectical proof procedures. In this thesis, we fill the gap by providing a dialectical discussion game for stable semantics. Since there could be more than one set of arguments that are selected with respect to complete semantics, we provide a more refined notion of the overall status of arguments based on the notion of a complete labelling and give the procedure to determine and defend the justification status. The approach is implemented by two dialectical proof procedures, namely the grounded discussion game and the preferred discussion game. Furthermore, argumentation can be viewed as a special form of logic programming with negation of failure, which leads to the question whether there exist correspondences between semantics in argumentation and semantics in logic programming. In this work, we show that the complete extensions in abstract argumentation coincide with the 3valued stable models in logic programming. Since many argumentation semantics can be described based on complete semantics and many logic programming semantics can be described based on 3-valued stable semantics, the correspondences between them lead to new possible correspondences, which enabled one to apply already existing algorithms and computational results of one area to the other area. One particular property of Dung’s abstract argumentation frameworks is that they do not consider the internal structure of arguments and the nature of the defeat relation. Various approaches have been proposed to instantiate Dung’s abstract argumentation framework. However, an important question is what postulates a proper instantiation of Dung’s theory should satisfy. There are several postulates that have been introduced, e.g., closure, direct consistency, indirect consistency, non-interference and crash resistance. In this thesis, we consider the ASPIC Lite system. We define the postulates of closure, direct consistency, indirect consistency, non-interference and crash resistance in the specific case of the ASPIC Lite formalism. Then we identity a set of conditions under which the ASPIC Lite system satisfies all the mentioned rationality postulates under complete semantics.