Welcome to our systempage, where we present our argumentation system ASPARTIX.
This page has been setup to present our current work on Argumentation
Frameworks (AF) under the
project "New
Methods for Analyzing, Comparing, and Solving Argumentation
Problems" (supported by the Wiener Wissenschafts-, Forschungs- und
Technologiefonds WWTF under
grant ICT
08-028).
Making Use of Advances in Answer-Set Programming for Abstract Argumentation Systems. Wolfgang Dvořák, Sarah Alice Gaggl, Johannes Wallner and Stefan Woltran.
has been accepted at the 19th International Conference on Applications of Declarative Programming and Knowledge Management (INAP 2011). [arXiv:1108.4942]Recent advances in ASP systems, in particular, the metasp optimization frontend for the ASP-package gringo/claspD provides direct commands to filter answer sets satisfying certain subset-minimality (or -maximality) constraints. This allows for much simpler encodings compared to the ones in standard ASP language. In this paper, we experimentally compare the original encodings (for the argumentation semantics based on preferred, semi-stable, and respectively, stage extensions) with new metasp encodings. Moreover, we provide novel encodings for the recently introduced resolution-based grounded semantics. Our experimental results indicate that the metasp approach works well in those cases where the complexity of the encoded problem is adequately mirrored within the metasp approach.
The encodings of the paper can be downloaded at Download identified as "metasp Encodings".
Over the last decade argumentation has become an important field in Artificial Intelligence (AI). At the momenten there are existing several different aproaches dealing with argumentation. In our current work we are following the aproach from Dung and the extensions from Amgoud, Cayrol and Bench-Capon. For detailed information please have a look at the References.
In the course of Sarah Gaggl's Masters Thesis "Solving Argumentation Frameworks using Answer Set Programming" a DLV program has been implemented. The current versions are available at Download.
With this implementation it is not only possible to compute the standard extensions for classical argumentation frameworks defined by Dung, but also for preference-based AF's (PAF's), value-based AF's (VAF's) and bipolar AF's (BAF's). In the latter case it is also possible to compute save and complete extensions, as well as distinguish between the classical d-admissible (following Dung), s-admissible (for stable) and c-admissible (for closed) extensions, for which also the respective preferred extensions are available.
Furthermore, we are able to provide encodings for semi-stable, ideal, stage, resolution-based grounded, cf2 and stage2 semantics.
Since we are actually working on this topic, this page may change constantly. We will consistently provide our newest results, so that it is worth to have a look at the Download section from time to time.
For the execution of the programs one needs an ASP solver like Gringo/Clasp(D) (see Potassco) or DLV (see DLVSYSTEM). Please note that the performance of the encodings highly depends on the ASP engine. At the moment the Potassco system gringo/Clasp(D) show the best performance.
Most of the encodings can be used for both systems, but for some of them an adjustment, due to some differences in the syntax of Gringo/Clasp, is necessary. Those encodings are specially marked. In the following we provide the encodings for all semantics (last update 15.10.2014 prefexDLV.dl, prefex_gringo.lp, semi_stableDLV.dl, semi_stable_gringo.lp, stage2.dl, stage2_gringo.lp, stage.dl, stage_gringo.lp):
* for ideal call DLV in the following way:
$ dlv ideal.dl input.dl -filter=ideal -n=1
$ gringo --reify pref_metasp.dl input.dl | \ gringo - {meta.lp,metaO.lp,metaD.lp}\ <(echo "optimize(1,1,incl).") | claspD 0
The input file (for example input.dl) should contain the arguments and attacks of the argumentation framework one wants to evaluate. For example the fact arg(a). encodes the argument a, and att(a,b). stands for the attack from a to b.
To run the ASPARTIX encodings with gringo/Clasp(D) one typically uses a call like:
$ gringo encodings.lp input.lp | clasp 0For example to enumerate all stable extensions:
$ gringo stable.lp input.lp | clasp 0For preferred, semi-stable, stage and stage2 semantics we need ClaspD. For example:
$ gringo prefex_gringo.lp input.lp | claspD 0
For DVL the call would look as follows (where encodings.dl is the respective encodings for the semantics):
$ dlv encodings.dl inputl.dl -filter=in
Here we provied some examples to test the program.
The input for an AFRA should be set up as follows. The fact afra(x). stands for an argument x, and the fact afraR(r,x,y). denotes the attack r=(x,y).
$ DLV afra.dl prefex.dl example_afra_bob.dl -filter=inThe -filter option filters out the predicates in(.) which denote the arguments contained in the preferred extension.
Here are some examples for the basic AF and some extensions:
For further informations please contact aspartix@dbai.tuwien.ac.at.
2011 | |
[15] |
Making Use of Advances in Answer-Set Programming for Abstract Argumentation Systems. Wolfgang Dvořák, Sarah Alice Gaggl, Johannes Wallner and Stefan Woltran INAP 2011 (technical paper) [arXiv:1108.4942] |
[14] |
Making Use of Advances in Answer-Set Programming for Abstract Argumentation Systems.
Wolfgang Dvořák, Sarah Gaggl, Johannes Wallner, and Stefan Woltran. Technical Report DBAI-TR-2011-70, Technische Universität Wien, 2011. [ bib | .pdf ] |
[13] |
Manifold Answer-Set Programs for Meta-Reasoning.
Wolfgang Faber and Stefan Woltran. In: M. Balduccini and T.C. Son (Eds.): Gelfond Festschrift, volumne 6565 of Lecture Notes in Artificial Intelligence, pages 44–63. Springer, Heidelberg (2011) [ bib ] |
2010 | |
[12] |
Analysis of Grounders and Solvers for ASP Encodings of
Argumentation Frameworks. Michael Petritsch. Bachelor Thesis, Technische Universität Wien, Stefan Woltran supervisor, 2010. [.pdf ] |
[11] |
cf2 Semantics Revisited. Sarah Gaggl and Stefan Woltran. In Pietro Baroni, Federico Cerutti, Massimiliano Giacomin, Guillermo R. Simari, editors, Proceedings of the Third International Conference on Computational Models of Argument (COMMA 2010), Desenzano del Garda, Italy, September 8-10, 2010, volume 216 of Frontiers in Artificial Intelligence and Applications, pages 243–254. IOS Press, 2010. [ bib |.pdf ] |
[10] |
ASPARTIX Conquers the Web
Uwe Egly, Sarah Gaggl Paul Wandl, and Stefan Woltran. Software demonstration at COMMA 2010. [.pdf] |
[9] |
Towards a General Argumentation System based on Answer-Set Programming. Sarah Gaggl. In ICLP (Technical Communications) 2010: 265-269.[pdf] |
[8] |
Answer-Set Programming Encodings for Argumentation Frameworks. Uwe Egly, Sarah Gaggl, and Stefan Woltran. In Argument and Computation, 1(2): 147 - 177 (2010).[ bib |pdf] |
2009 | |
[7] |
ASPARTIX: A System for Computing Different Argumentation
Semantics in Answer-Set Programming. Sarah Gaggl. Poster. ACAI'09 Poster Session. [.pdf ] |
[6] |
Manifold Answer-Set Programs for Meta-Reasoning.
Wolfgang Faber and Stefan Woltran. In Proceedings of the 10th International Conference on Logic Programming and Nonmonotonic Reasoning, (LPNMR'09), Potsdam, Germany, September 14-18, 2009. [ bib | .pdf ] |
[5] |
Manifold Answer-Set Programs for Meta-Reasoning.
Wolfgang Faber and Stefan Woltran. In Proceedings of the IJCAI-09 Workshop on Nonmonotonic Reasoning, Action and Change, (NRAC'09). [.pdf ] |
[4] |
Solving Argumentation Frameworks using Answer Set Programming.
Sarah Gaggl. Masters Thesis, Technische Universität Wien, 2009 [.pdf ] |
2008 | |
[3] |
ASPARTIX: Implementing Argumentation Frameworks Using Answer-Set Programming.
Uwe Egly, Sarah Gaggl, and Stefan Woltran. In Maria G. de la Banda and Enrico Pontelli, editors, Proceedings of the Twenty-Fourth International Conference on Logic Programming, (ICLP'08), Udine, Italy, December 9-13, 2008, volume 5366 of Lecture Notes in Computer Science, pages 734–738. Springer, 2008. [ bib | .pdf ] |
[2] |
Answer-Set Programming Encodings for Argumentation Frameworks.
Uwe Egly, Sarah Gaggl, and Stefan Woltran. In 1st Workshop on Answer Set Programming and Other Computing Paradigms (ASPOCP 2008), Udine, Italy, 2008 [ bib | .pdf ] |
[1] |
Answer-Set Programming Encodings for Argumentation Frameworks.
Uwe Egly, Sarah Gaggl, and Stefan Woltran. Technical Report DBAI-TR-2008-62, Technische Universität Wien, 2008 [ bib | .pdf ] |