Formal Identification of Argumentation Patterns in Scientific Texts

Abstract

In this paper we present the methods for the automatic identification of argumentation patterns and the results of their application. These methods have been employed to analyze argumentation annotations of 25 scientific texts from two thematic areas. Under study were the expert annotations constructed manually with the help of web tools for visualizing argumentative statements and argumentation schemes, as well as for modelling the argumentation structure of a text as an oriented graph. Such graphs contain two node types: information nodes denoting statements and their connecting reasoning models (schemas) from Walton's compendium. The regularly employed reasoning models and their structural combinations (argumentation subgraphs) form argumentation patterns. Patterns containing more than one scheme are unmarked in initial graphs. As a result of processing argumentation annotations from the collection, we have constructed a joint spectrum of argumentation patterns with their absolute and text frequencies. The methods of frequent subgraph mining have been used to identify argumentation patterns containing three or more schemes. The subgraph matching has been performed through the use of the NetworkX package which implements the VF2 algorithm for subgraph isomorphism testing. We have analyzed the calculated frequencies to identify both the general principles behind the use of argumentation patterns typical of scientific texts, as well as the specific tendencies of their functioning within distinct thematic areas (linguistics and computer science). These general principles regulate the use of both separate schemes and their structural combinations. The latter appear in two configuration types: either as sequencies of argumentation schemes (up to 5 elements) or as tree structures (which contain up to 8 nodes). Specifically, we demonstrate that branching within a tree-form pattern typically presupposes the parallel use of identical argumentation schemes. Additionally, branching of argumentation patterns occurs more often in proximity to the main thesis of a text, than near the initial premises. Finally, the thematic area can condition not only the use of separate schemes, but also their structural combination within complex patterns. The results obtained are applicable to the evaluation of text similarity based on argumentation patterns employed in them, which, in its turn, can improve the clustering and classification of texts, evaluation of their persuasiveness, as well as the formal synthesis of argumentation.