The investigation of computational models of argument is a rich, interdisciplinary, and fascinating research field whose ultimate aim is to support the development of computer-based systems able to engage argumentation-related activities with human users or among themselves. This ambitious research goal involves the study of natural, artificial, and theoretical argumentation and, as such, requires openness to interactions with a variety of disciplines ranging from philosophy and cognitive science to formal logic and graph theory, to mention some.

The biennial International Conference on Computational Models of Argument (COMMA), reaching its sixth edition, provides since ten years a dedicated forum for presentation of the latest advancements in this multifaceted field, covering both basic research and innovative applications.

The first COMMA was supported by the EU 6th Framework Programme project ASPIC and was hosted by the University of Liverpool in 2006 with a vision for the future. After the event, a steering committee promoting the continuation of the conference was established and, since then, the steady growth of interest in computational argumentation research worldwide has gone hand in hand with the development of the conference itself and of related activities by its community.

Since the second edition, organized by IRIT in Toulouse in 2008, plenary invited talks by world-leading researchers and a software demonstration session became an integral part of the conference program.

The third edition, organized in 2010 by the University of Brescia in Desenzano del Garda, saw the addition of a best student paper award. The same year, the new journal Argument and Computation, closely related to the COMMA community, was started.

Since the fourth edition, organized by the Vienna University of Technology in 2012, an Innovative Application Track and a section for Demonstration Abstracts were included in the proceedings.

At the fifth edition, co-organized in 2014 by the Universities of Aberdeen and Dundee in Pitlochry, the main conference was preceded by the first Summer School on Argumentation: Computational and Linguistic Perspectives. The same year, the first International Competition on Computational Models of Argumentation, to be held in 2015, was launched.

This year COMMA is hosted by the University of Potsdam and the conference program is complemented by two satellite workshops, in addition to the second edition of the summer school. Moreover, reflecting the evolution of research publishing worldwide, COMMA 2016 proceedings will be Open Access.

The evolution of COMMA into an articulated event, however, is only subsidiary to the fulfillment of its mission, namely documenting and stimulating the advancement of knowledge and the development of applications in the field.

The past conference programs, along with the present one, give comfortable indications in this respect.

First of all, they have seen, since the very first edition, a balanced blend of theoretical and application-oriented works.

Further, in addition to “traditional” investigation topics in the field, like abstract argumentation frameworks, the conference has always included contributions concerning emerging trends and the development of new connections with other areas.

Among them, it is possible to mention the investigation of a variety of quantitative approaches to argumentation, in relationship with Bayesian networks, probability theory, or fuzzy logic. Also, we wish to mention the area of argument mining, the automatic detection and analysis of argumentation in linguistic data. While the term was barely known three years ago, this research has emerged as a fast-growing subfield of Computational Linguistics (CL), with a variety of specialized workshops having been formed over the past few years, and the topic has also been established in important CL conferences. So far, following the general trend in CL, the methods being applied to argument mining largely rely on machine learning over surface-oriented features of text; but there seems to be great potential in linking the text analysis also to the “deeper” phenomena – reasoning and inference – that render an argumentation plausible.

We conclude by remarking that the success of a conference depends on the contributions of many people.

We acknowledge steady support and encouragement by the COMMA Steering Committee.

We would like to thank the invited speakers, Jens Allwood, Anthony Hunter, and Marie-Francine Moens, for accepting our invitation and for witnessing, once again, the rich diversity of this area with their talks, covering respectively an insightful analysis of the normative and descriptive perspectives in argumentation studies, the promise and challenge of using computational persuasion for applications in behaviour change, and the formidable question of how can a machine acquire world and common sense knowledge for argument mining.

We are deeply grateful to the members of the Program Committee and to the additional reviewers for their invaluable efforts. Their reports and subsequent discussions led to the selection, out of 63 submissions, of 25 full papers and 17 short papers, to be included in the conference proceedings together with 10 demonstration abstracts. The submission and reviewing process has been managed through the Easychair conference system, which we acknowledge for supporting COMMA since the first edition.

Last but not least, we thank all the authors for contributing to the success of the conference with their hard work and commitment.

Berlin/Brescia/Potsdam, July 2016

Pietro Baroni (Program chair)

Thomas F. Gordon (Conference chair)

Tatjana Scheffler (Local organization co-chair)

Manfred Stede (Conference chair)