Argumentation Patterns

Attacks semantics conceptualizes abstract argumentation in terms of successful and unsuccessful attacks, such that arguments are accepted when there are no successful attacks on them.

The followig poster provides an overview of the proposed semantics, the challenges we are faced with, and the open issues.
Poster about attack semantics

We are implementing a prototype of the SCC recursive schema for attack semantics, using the algorthm we proposed in [Villata et al. IJCAI 2011].

The prototype has been developed using Python programming language v2.6., an interpreted, general-purpose high-level programming language, whose reference implementation (CPython) is an open source software. In particular, we are using python.graph package, and exploiting its inner built-in features (e.g., search and traversal algorithms, cycle detection). In our implementation, the argumentation framework is a directed graph and the available SCCs are associated to the arguments attacking them, using dictionaries and lists.

The argumentation framework is characterized by the following structures:
1. a directed graph called digraph;
2. a list of strongly connected components. This is represented by means of a list of lists, each of them containing the nodes of the SCC itself;
3. a dictionary implementing the base function. The SCCs are the keys of the dictionary, and the arguments attacking each SCC are its values. We use two algorithms classes provided by python.graph, concerning searching (e.g., depth first searching used for breadth-first search) and accessibility.

PROTOTYPE