| Author | Title | Year | Journal/Proceedings | Reftype | DOI/URL |
|---|---|---|---|---|---|
| Song, I. & Governatori, G. | Nested Rules in Defeasible Logic. | 2005 | RuleML | inproceedings | DOI |
| Abstract: Defeasible Logic is a rule-based non-monotonic logic with tractable reasoning services. In this paper we extend Defeasible Logic with nested rules. We consider a new Defeasible Logic, called DL$^ns$, where we allow one level of nested rules. A nested rule is a rule where the antecedent or the consequent of the rule are rules themselves. The inference conditions for DL$^ns$ are based on reflection on the inference structures (rules) of the particular theory at hand. Accordingly DL$^ns$ can be considered an amalgamated reflective system with implicit reflection mechanism. Finally we outline some possible applications of the logic. | |||||
BibTeX:
@inproceedings{ruleml05insu,
author = {Insu Song and Guido Governatori},
title = {Nested Rules in Defeasible Logic.},
booktitle = {RuleML},
publisher = {Springer},
year = {2005},
volume = {3791},
pages = {204-208},
doi = {http://dx.doi.org/10.1007/11580072_18}
}
|
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| Artosi, A., Cattabriga, P. & Governatori, G. | KED: A Deontic Theorem Prover | 1994 | Workshop on Legal Application of Logic Programming | inproceedings | |
| Abstract: Deontic logic (DL) is increasingly recognized as an indispensable tool in such application areas as formal representation of legal knowledge and reasoning, formal specification of computer systems and formal analysis of database integrity constraints. Despite this acknowledgement, there have been few attempts to provide computationally tractable inference mechanisms for DL. In this paper we shall be concerned with providing a computationally oriented proof method for standard DL (SDL), i.e., normal systems of modal logic with the usual possible-worlds semantics. Because of the natural and easily implementable style of proof construction it uses, this method seems particularly well-suited for applications in the AI and Law field, and though in the present version it works for SDL only, it forms an appropriate basis for developing efficient proof methods for more expressive and sophisticated extensions of SDL. | |||||
BibTeX:
@inproceedings{ACG94a,
author = {Artosi, Alberto and Cattabriga, Paola and Guido Governatori},
title = {{KED}: A Deontic Theorem Prover},
booktitle = {Workshop on Legal Application of Logic Programming},
publisher = {IDG},
year = {1994},
pages = {60-76}
}
|
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| Artosi, A., Cattabriga, P. & Governatori, G. | An Automated Approach to Normative Reasoning | 1994 | Artificial Normative Reasoning | inproceedings | |
| Abstract: It is by now generally accepted in the Artificial Intelligence and Law field that many aspects of normative language and reasoning can be modelled in deontic logics based on modal logic. This obviously implies the need for computationally tractable inference mechanisms for Deontic Logic. In this paper we shall be concerned with developing a computationally oriented proof method for several normal (in Åqvist classification normal and strongly normal) deontic logics. Since this method is arguably more natural and intuitive than other (e.g. resolution or translation based) proof methods, and it leads to simple and easy implementable procedures, it seems particularly well-suited for applications in the newly developed area of ``artificial normative reasoning''. Moreover, though in the present version it works for deontic logics of the simplest kind, it is sufficiently generic and flexible to provide an appropriate algorithmic proof framework for deontic logics of greater richness and complexity. | |||||
BibTeX:
@inproceedings{ACG94b,
author = {Artosi, Alberto and Cattabriga, Paola and Guido Governatori},
title = {An Automated Approach to Normative Reasoning},
booktitle = {Artificial Normative Reasoning},
year = {1994},
pages = {132-145}
}
|
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| Artosi, A., Governatori, G. & Sartor, G. | Towards a Computational Treatment of Deontic Defeasibility | 1996 | Deontic Logic Agency and Normative Systems | inproceedings | |
| Abstract: In this paper we describe an algorithmic framework for a multi-modal logic arising from the combination of the system of modal (epistemic) logic devised by Meyer and van der Hoek for dealing with nonmonotonic reasoning with a deontic logic of the Jones and Pörn-type. The idea behind this (somewhat eclectic) formal set-up is to have a modal framework expressive enough to model certain kinds of deontic defeasibility, in particular by taking into account preferences on norms. The appropriate inference mechanism is provided by a tableau-like modal theorem proving system which supports a proof method closely related to the semantics of modal operators. We argue that this system is particularly well-suited for mechanizing nonmonotonic forms of inference in a monotonic multi-modal setting. | |||||
BibTeX:
@inproceedings{AGS96,
author = {Artosi, Alberto and Governatori, Guido and Sartor, Giovanni},
title = {Towards a Computational Treatment of Deontic Defeasibility},
booktitle = {Deontic Logic Agency and Normative Systems},
publisher = {Springer-Verlag},
year = {1996},
pages = {27-46}
}
|
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| Antoniou, G., Billington, D., Governatori, G. & Maher, M. J. | A flexible framework for defeasible logics | 2000 | Proc. American National Conference on Artificial Intelligence (AAAI-2000) | inproceedings | URL |
| Abstract: Logics for knowledge representation suffer from over-specialization: while each logic may provide an ideal representation formalism for some problems, it is less than optimal for others. A solution to this problem is to choose from several logics and, when necessary, combine the representations. In general, such an approach results in a very difficult problem of combination. However, if we can choose the logics from a uniform framework then the problem of combining them is greatly simplified. In this paper, we develop such a framework for defeasible logics. It supports all defeasible logics that satisfy a strong negation principle. We use logic meta-programs as the basis for the framework. | |||||
BibTeX:
@inproceedings{aaai2000,
author = {Antoniou, Grigoris and Billington, David and Governatori, Guido and Maher, Michael J.},
title = {A flexible framework for defeasible logics},
booktitle = {Proc. American National Conference on Artificial Intelligence (AAAI-2000)},
publisher = {AAAI/MIT Press},
year = {2000},
pages = {401-405},
url = {http://www.aaai.org/Press/Proceedings/AAAI/2000/aaai2000.html}
}
|
|||||
| Maher, M. J. & Governatori, G. | A semantic decomposition of defeasible logic | 1999 | Proc. American National Conference on Artificial Intelligence (AAAI-99) | inproceedings | URL |
| Abstract: We investigate defeasible logics using a technique which decomposes the semantics of such logics into two parts: a specification of the structure of defeasible reasoning and a semantics for the meta-language in which the specification is written. We show that Nute's Defeasible Logic corresponds to Kunen's semantics, and develop a defeasible logic from the well-founded semantics of Van Gelder, Ross and Schlipf. We also obtain a new defeasible logic which extends an existing language by modifying the specification of Defeasible Logic. Thus our approach is productive in analysing, comparing and designing defeasible logics. | |||||
BibTeX:
@inproceedings{aaai99,
author = {Maher, Michael J. and Governatori, Guido},
title = {A semantic decomposition of defeasible logic},
booktitle = {Proc. American National Conference on Artificial Intelligence (AAAI-99)},
publisher = {AAAI Press},
year = {1999},
pages = {299-305},
url = {http://www.aaai.org/Press/Proceedings/AAAI/1999/aaai1999.html}
}
|
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| Antoniou, G., Billington, D., Governatori, G. & Maher, M. J. | On the Modeling and Analysis of Regulations | 1999 | Proceedings of the Australian Conference Information Systems | inproceedings | URL |
| Abstract: Regulations are a wide-spread and important part of government and business. They codify how products must be made and processes should be performed. Such regulations can be difficult to understand and apply. In an environment of growing complexity of, and change in, regulation, automated support for reasoning with regulations is becoming increasingly necessary. In this paper we report on ongoing work which aims at providing automated support for the drafting and use of regulations using logic modelling techniques. We highlight the support that can be provided by logic modelling, describe the technical foundation of our project, and report on the status of the project and the next steps. | |||||
BibTeX:
@inproceedings{acis,
author = {Antoniou, Grigoris and Billington, David and Governatori, Guido and Maher, Michael J.},
title = {On the Modeling and Analysis of Regulations},
booktitle = {Proceedings of the Australian Conference Information Systems},
year = {1999},
pages = {20-29},
url = {http://www.vuw.ac.nz/acis99/Papers/PaperGovernatori-088.pdf}
}
|
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| Artosi, A., Benassi, P., Governatori, G. & Rotolo, A. | Shakespearian modal logic: A Labelled Treatment of Modal Identity | 1998 | Advances in Modal Logic. Volume 1 | incollection | URL |
| Abstract: In this paper we describe a modal proof system arising from the combination of a tableau-like classical system, which incorporates a restricted (``analytical'') version of the cut rule, with a label formalism which allows for a specialised, logic dependant unification algorithm. The system provides a uniform proof-theoretical treatment of first-order (normal) modal logics with identity, with and without Barcan formula and/or its converse | |||||
BibTeX:
@incollection{advances,
author = {Artosi, Alberto and Benassi, Paola and Governatori, Guido and Rotolo, Antonino},
title = {Shakespearian modal logic: A Labelled Treatment of Modal Identity},
booktitle = {Advances in Modal Logic. Volume 1},
publisher = {CSLI Publications},
year = {1998},
pages = {1-21},
url = {http://cslipublications.stanford.edu/site/157586102X.html}
}
|
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| Governatori, G., ter Hofstede, A. H. & Oaks, P. | Is Defeasible Logic Applicable? | 2001 | Proceedings of the 2nd Australasian Workshop on Computational Logic | inproceedings | |
| Abstract: In this paper the application of defeasible logic for automated negotiation is investigated. Defeasible logic is flexible enough to be adapted to several possible negotiation strategies, has efficient implementations, and provides a formal basis for analysis (e.g. to explain why a negotiation was not successful). Two case studies, one small and one more comprehensive, will be described and the feasibility of approaches based on defeasible logic will be discussed. | |||||
BibTeX:
@inproceedings{awcl-paper,
author = {Governatori, Guido and Arthur H.M. ter Hofstede and Oaks, Phillipa},
title = {Is Defeasible Logic Applicable?},
booktitle = {Proceedings of the 2nd Australasian Workshop on Computational Logic},
publisher = {Queensland University of Technology},
year = {2001},
pages = {47-62}
}
|
|||||
| Governatori, G., ter Hofstede, A. H. & Oaks, P. | Defeasible Logic for Automated Negotiation | 2000 | Proceedings of CollECTeR | inproceedings | |
| Abstract: Negotiation plays a fundamental role in e-commerce. In this paper, the application of defeasible logic for automated negotiation is investigated. Defeasible logic is flexible enough to be adapted to several possible negotiation strategies, has efficient implementations, and provides a formal basis for analysis (e.g. to explain why a negotiation was not successful). Two case studies, one small and one more comprehensive, will be described and the feasibility of approaches based on defeasible logic will be discussed. | |||||
BibTeX:
@inproceedings{collecter,
author = {Governatori, Guido and ter Hofstede, Arthur H.M. and Oaks, Phillipa},
title = {Defeasible Logic for Automated Negotiation},
booktitle = {Proceedings of CollECTeR},
publisher = {Deakin University},
year = {2000},
note = {Published on CD}
}
|
|||||
| Artosi, A. & Governatori, G. | A tableaux methodology for deontic conditional logics | 1998 | $EON'98, 4$^th$ International Workshop on Deontic Logic in Computer Science | inproceedings | URL |
| Abstract: In this paper we present a theorem proving methodology for a restricted but significant fragment of the conditional language made up of (boolean combinations of) conditional statements with unnested antecedents. The method is based on the possible world semantics for conditional logics. The label formalism introduced in tecade,jelia to account for the semantics of normal modal logics is easily adapted to the semantics of conditional logics by simply indexing labels with formulas. The inference rules are provided by the propositional system $KE^+$ --- a tableau-like analytic proof system devised to be used both as a refutation and a direct method of proof --- enlarged with suitable elimination rules for the conditional connective. The theorem proving methodology we are going to present can be viewed as a first step towards developing an appropriate algorithmic framework for several conditional logics for (defeasible) conditional obligation. | |||||
BibTeX:
@inproceedings{deon,
author = {Artosi, Alberto and Governatori, Guido},
title = {A tableaux methodology for deontic conditional logics},
booktitle = {$\Delta$EON'98, 4$^{th}$ International Workshop on Deontic Logic in Computer Science},
publisher = {CIRFID},
year = {1998},
pages = {65-81},
url = {http://arXiv.org/cs.LO/0003050}
}
|
|||||
| Gabbay, D. M. & Governatori, G. | Dealing with Label Dependent Deontic Modalities | 1998 | Norms, Logics and Information Systems. New Studies in Deontic Logic | incollection | |
| Abstract: In this paper, following Scott's advice, we argue that normative reasoning can be represented in a multi-setting framework; in particular in a multi-modal one, where modalities are indexed. Indexed modalities can model several aspects involved in normative reasoning. Systems are combined using Gabbay's fibring methodology which provides complete semantics that can be used to model a labelled tableau-like proofs system. | |||||
BibTeX:
@incollection{deon98,
author = {Dov M. Gabbay and Governatori, Guido},
title = {Dealing with Label Dependent Deontic Modalities},
booktitle = {Norms, Logics and Information Systems. New Studies in Deontic Logic},
publisher = {IOS Press},
year = {1998},
pages = {311-330}
}
|
|||||
| Governatori, G. & Maher, M. J. | An Argumentation-Theoretic Characterization of Defeasible Logic | 2000 | ECAI 2000. Proceedings of the 14th European Conference on Artificial Intelligence | inproceedings | |
| Abstract: Defeasible logic is an efficient non-monotonic logic that is defined only proof-theoretically. It has potential application in some legal domains. We present here an argumentation semantics for defeasible logic that will be useful in these applications. Our development differs at several points from existing argumentation frameworks since there are several features of defeasible logic that have not been addressed in the literature. | |||||
BibTeX:
@inproceedings{ecai2000-2,
author = {Governatori, Guido and Maher, Michael J.},
title = {An Argumentation-Theoretic Characterization of Defeasible Logic},
booktitle = {ECAI 2000. Proceedings of the 14th European Conference on Artificial Intelligence},
publisher = {IOS Press},
year = {2000},
pages = {469-474}
}
|
|||||
| Antoniou, G., Billington, D., Governatori, G., Maher, M. J. & Rock, A. | A Family of Defeasible Reasoning Logics and its Implementation | 2000 | ECAI 2000. Proceedings of the 14th European Conference on Artificial Intelligence | inproceedings | |
| Abstract: Defeasible reasoning is a direction in nonmonotonic reasoning that is based on the use of rules that may be defeated by other rules. It is a simple, but often more efficient approach than other nonmonotonic reasoning systems. This paper presents a family of defeasible reasoning formalisms built around Nute's defeasible logic. We describe the motivations of these formalisms and derive some basic properties and interrelationships. We also describe a query answering system that supports these formalisms and is available on the World Wide Web. | |||||
BibTeX:
@inproceedings{ecai2000-5,
author = {Antoniou, Grigoris and Billington, David and Governatori, Guido and Maher, Michael J. and Rock, Andrew},
title = {A Family of Defeasible Reasoning Logics and its Implementation},
booktitle = {ECAI 2000. Proceedings of the 14th European Conference on Artificial Intelligence},
publisher = {IOS Press},
year = {2000},
pages = {459-463}
}
|
|||||
| Di Giusto, P. & Governatori, G. | A New Approach to Base Revision | 1999 | Progress in Artificial Intelligence | inproceedings | URL |
| Abstract: We present three approaches to revision of belief bases, which are also examined in the case in which the sentences in the base are partitioned between those which can and those which cannot be changed; the approaches are shown to be semantically equivalent. A new approach is then presented, based on the modification of individual rules, instead of deletion. The resulting base is semantically equivalent to that generated by the other approaches, in the sense that it has the same models, but the rule part alone has fewer models, that is, is subjected to a smaller change. | |||||
BibTeX:
@inproceedings{epia1,
author = {Di Giusto, Paolo and Governatori, Guido},
title = {A New Approach to Base Revision},
booktitle = {Progress in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {1999},
number = {1695},
pages = {327-341},
url = {http://springerlink.metapress.com/index/FEM2H5B5FXWN3QNM}
}
|
|||||
| Di Giusto, P. & Governatori, G. | Analytic modal revision for multi-agent systems | 1999 | Progress in Artificial Intelligence | inproceedings | URL |
| Abstract: We present two models of hierarchical structured multi-agents, and we describe how to obtain a modal knowledge base from distributed sources. We then propose a computationally oriented revision procedure for modal knowledge bases. This procedure is based on a labelled tableaux calculi supplemented with a formalism to record the dependencies of the formulae. The dependencies are then used to reconstruct the minimal inconsistent sets, and the sub-formulae responsible for the inconsistencies are revised according to well-defined chains of modal functions. | |||||
BibTeX:
@inproceedings{epia2,
author = {Di Giusto, Paolo and Governatori, Guido},
title = {Analytic modal revision for multi-agent systems},
booktitle = {Progress in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {1999},
number = {1695},
pages = {282-296},
url = {http://springerlink.metapress.com/index/Y9FQD8JXTTN7N9YG}
}
|
|||||
| Governatori, G. | Labelling Ideality and Subideality | 1996 | Practical Reasoning | inproceedings | |
| Abstract: In this paper we suggest ways in which logic and law may usefully relate; and we present an analytic proof system dealing with the Jones Pörn's deontic logic of Ideality and Subideality, which offers some suggestions about how to embed legal systems in label formalism. | |||||
BibTeX:
@inproceedings{fapr,
author = {Governatori, Guido},
title = {Labelling Ideality and Subideality},
booktitle = {Practical Reasoning},
publisher = {Springer-Verlag},
year = {1996},
number = {1085},
pages = {291-304}
}
|
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| Gabbay, D. M. & Governatori, G. | Fibred Modal Tableaux | 2000 | Labelled Deduction | incollection | |
| Abstract: We describe a general and uniform tableau methodology for multi-modal logics arising from Gabbay's methodology of fibring and Governatori's labelled tableau system | |||||
BibTeX:
@incollection{fmt,
author = {Dov M. Gabbay and Governatori, Guido},
title = {Fibred Modal Tableaux},
booktitle = {Labelled Deduction},
publisher = {Kluwer},
year = {2000},
volume = {17},
pages = {163-194}
}
|
|||||
| Gabbay, D. M. & Governatori, G. | Fibred Modal Tableaux (Preliminary Report) | 1998 | Tableaux'98: Position Papers | inproceedings | |
| Abstract: We describe a general and uniform tableau methodology for multi-modal logics arising from Gabbay's methodology of fibring and Governatori's labelled tableau system | |||||
BibTeX:
@inproceedings{fmt-old,
author = {Dov M. Gabbay and Governatori, Guido},
title = {Fibred Modal Tableaux (Preliminary Report)},
booktitle = {Tableaux'98: Position Papers},
year = {1998},
pages = {33-48}
}
|
|||||
| Governatori, G. | A Duplication and Loop Checking Free System for S4 | 1996 | 5$^th$ Workshop on Theorem Proving with Analytic Tableaux and Related Methods (Short Papers) | inproceedings | |
| Abstract: Most of the sequent/tableau based proof systems for the modal logic S4 need to duplicate formulas and thus are required to adopt some method of loop checking. In what follows we present a tableau-like proof system for S4, based on D'Agostino and Mondadori's classical KE, which is free of duplication and loop checking. The key feature of this system (let us call it KES4) consists in its use of (i) a label formalism which models the semantics of the modal operators according to the usual conditions for S4; and (ii) a label unification scheme which tells us when two labels ``denote'' the same world in the S4-model(s) generated in the course of proof search. Moreover, it uses special closure conditions to check models for putative contradictions. | |||||
BibTeX:
@inproceedings{gov:tab96,
author = {Governatori, Guido},
title = {A Duplication and Loop Checking Free System for {S4}},
booktitle = {5$^{th}$ Workshop on Theorem Proving with Analytic Tableaux and Related Methods (Short Papers)},
publisher = {Universit\`a di Milano},
year = {1996},
number = {Technical Report 154-96},
pages = {19-32}
}
|
|||||
| Governatori, G. & Rotolo, A. | Labelled Modal Sequents | 2000 | Position Papers and Tutorials, TABLEAUX 2000 | inproceedings | |
| Abstract: In this paper we present a new labelled sequent calculus for modal logic. The proof method works with a more ``liberal'' modal language which allows inferential steps where different formulas refer to different labels without moving to a particular world and there computing if the consequence holds. World-paths can be composed, decomposed and manipulated through unification algorithms and formulas in different worlds can be compared even if they are sub-formulas which do not depend directly on the main connective. Accordingly, such a sequent system can provide a general definition of modal consequence relation. Finally, we briefly sketch a proof of the soundness and completeness results. | |||||
BibTeX:
@inproceedings{lms:tab2000,
author = {Governatori, Guido and Rotolo, Antonino},
title = {Labelled Modal Sequents},
booktitle = {Position Papers and Tutorials, TABLEAUX 2000},
publisher = {School of Computer Science, University of St Andrews},
year = {2000},
number = {Scientific Report CS/00/001},
pages = {3-21}
}
|
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| Artosi, A., Cattabriga, P. & Governatori, G. | A Prolog Implementation of KEM | 1995 | Proceedings of GULP-PRODE'95 | inproceedings | |
| Abstract: In this paper, we describe a Prolog implementation of a new theorem prover for (normal propositional) modal and multi--modal logics. The theorem prover, which is called $KEM$, arises from the combination of a classical refutation system which incorporates a restricted (``analytica'') version of the cut rule with a label formalism which allows for a specialised logic--dependent unification algorithm. An essential feature of $KEM$ is that it yields a rather simple and efficient proof search procedure which offers many computational advantages over the usual tableau-based proof search methods. This is due partly to the use of linear 2--premise $ rules in place of the branching $ rules of the standard tableau method, and partly to the crucial role played by the analytic cut (the only branching rule) in eliminating redundancy from the search space. It turns out that $KEM$ method of proof search is not only computationally more efficient but also intuitivelly more natural than other (e.g. resolution-based) methods leading to simple and easy implementable procedures (two $KEM$ Theorem Prover-like systems have been implemented: an LPA interpreter on Macintosh, and a Quintus compiler on Sun-Sparcstation) which make it well suited for efficient automated proof search in modal logic. | |||||
BibTeX:
@inproceedings{gulp,
author = {Artosi, Alberto and Cattabriga, Paola and Governatori, Guido},
title = {A Prolog Implementation of {KEM}},
booktitle = {Proceedings of GULP-PRODE'95},
publisher = {Universit{\`a} di Salerno},
year = {1995},
pages = {395-400}
}
|
|||||
| Governatori, G., Dumas, M., ter Hofstede, A. H. & Oaks, P. | A formal approach to protocols and strategies for (legal) negotiation | 2001 | Procedings of the 8th International Conference on Artificial Intelligence and Law | inproceedings | DOI |
| Abstract: We propose a formal and executable framework for expressing protocols and strategies for automated (legal) negotiation. In this framework a party involved in a negotiation is represented through a software agent composed of four modules: (i) a communication module which manages the interaction with the other agents; (ii) a control module; (iii) a reasoning module specified as a defeasible theory; and (iv) a knowledge base which bridges the control and the reasoning modules, while keeping track of past decisions and interactions. The choice of defeasible logic is justified against a set of desirable criteria for negotiation automation languages. Moreover, the suitability of the framework is illustrated through two case studies. | |||||
BibTeX:
@inproceedings{icail,
author = {Governatori, Guido and Dumas, Marlon and Arthur H.M. ter Hofstede and Phillipa Oaks},
title = {A formal approach to protocols and strategies for (legal) negotiation},
booktitle = {Procedings of the 8th International Conference on Artificial Intelligence and Law},
publisher = {ACM Press},
year = {2001},
pages = {168-177},
doi = {http://dx.doi.org/10.1145/383535.383555}
}
|
|||||
| Governatori, G. |
Ideality and Subideality from a Computational Point of View [BibTeX] |
1998 | From Practical Reason to Legal Computer Science. Legal Computer Science | incollection | |
BibTeX:
@incollection{ivr,
author = {Governatori, Guido},
title = {Ideality and Subideality from a Computational Point of View},
booktitle = {From Practical Reason to Legal Computer Science. Legal Computer Science},
publisher = {Clueb},
year = {1998},
volume = {Part II},
pages = {315-329}
}
|
|||||
| Artosi, A., Benassi, P., Governatori, G. & Rotolo, A. | Labelled proofs for quantified modal logic | 1996 | Logics in Artificial Intelligence | inproceedings | |
| Abstract: In this paper we describe a modal proof system arising from the combination of a tableau-like classical system, which incorporates a restricted (``analytic'') version of the cut rule, with a label formalism which allows for a specialised, logic-dependent unification algorithm. The system provides a uniform proof-theoretical treatment of first-order (normal) modal logics with and without the Barcan Formula and/or its converse. | |||||
BibTeX:
@inproceedings{jelia,
author = {Artosi, Alberto and Benassi, Paola and Governatori, Guido and Rotolo, Antonino},
title = {Labelled proofs for quantified modal logic},
booktitle = {Logics in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {1996},
number = {1126},
pages = {70-86}
}
|
|||||
| Artosi, A., Governatori, G. & Rotolo, A. | Labelled Tableaux for Non-monotonic Reasoning: Cumulative Consequence Relations | 2002 | Journal of Logic and Computation | article | DOI |
| Abstract: In this paper we present a labelled proof method for computing nonmonotonic consequence relations in a conditional logic setting. The method exploits the strong connection between these deductive relations and conditional logics, and it is based on the usual possible world semantics devised for the latter. The label formalism introduced to account for the semantics of normal modal logics, is easily adapted to the semantics of conditional logic by simply indexing labels with formulas. The basic inference rules are provided by the propositional system $+$ ---a tableau-like analytic proof system devised to be used both as a refutation method and a direct method of proof--- that is the classical core of KEM which is thus enlarged with suitable elimination rules for the conditional connective. The resulting algorithmic framework is able to compute cumulative consequence relations in so far as they can be expressed as conditional implications. | |||||
BibTeX:
@article{jlc,
author = {Artosi, Alberto and Governatori, Guido and Rotolo, Antonino},
title = {Labelled Tableaux for Non-monotonic Reasoning: Cumulative Consequence Relations},
journal = {Journal of Logic and Computation},
year = {2002},
volume = {12},
number = {6},
pages = {1027-1060},
doi = {http://dx.doi.org/10.1093/logcom/12.6.1027}
}
|
|||||
| Governatori, G. & Stranieri, A. | Towards the Application of Association Rules for Defeasible Rules Discovery | 2001 | Legal Knowledge and Information Systems | inproceedings | URL |
| Abstract: In this paper we investigate the feasibility of Knowledge Discovery from Database (KDD) in order to facilitate the discovery of defeasible rules that represent the ratio decidendi underpinning legal decision making. Moreover we will argue in favour of Defeasible Logic as the appropriate formal system in which the extracted principles should be encoded. | |||||
BibTeX:
@inproceedings{jurix,
author = {Governatori, Guido and Stranieri, Andrew},
title = {Towards the Application of Association Rules for Defeasible Rules Discovery},
booktitle = {Legal Knowledge and Information Systems},
publisher = {IOS Press},
year = {2001},
pages = {63-75},
url = {http://www.jurix.nl/pdf/j01-06.pdf}
}
|
|||||
| Governatori, G. | KE+: Beyond Refutation | 1995 | KI-95 Activities: Workshops, Posters, Demos | inproceedings | |
| Abstract: The system KE+, a tableau-like proof system based on D'Agostino-Mondadori KE, is presented in this paper. This system avoids some of the drawbacks of other proof methods. In fact it is completly analytical, it is able to detect whether a formula is either a tautology or a contradiction or only a satisfiable one; in the course of a proof it can detect whether a subformula is a tautology and it uses this fact in the proof of the main formula | |||||
BibTeX:
@inproceedings{ke+,
author = {Governatori, Guido},
title = {KE+: Beyond Refutation},
booktitle = {KI-95 Activities: Workshops, Posters, Demos},
year = {1995},
pages = {75-76}
}
|
|||||
| Artosi, A., Cattabriga, P. & Governatori, G. | A Modal Computational Framework for Default Reasoning | 1997 | Proceedings of KI-97 | inproceedings | |
| Abstract: Usually a default rule A : B/C is intended to mean that if A holds in a state of affairs a B is consistent, then C follows by default. However, C is not a necessary conclusion: different states of affairs are possible (conceivable). According to this view, Meyer and van der Hoek developed a multimodal logic, called S5P(n), for treating non-monotonic reasoning in a monotonic setting. In this paper we shall describe a proof search algorithm for S5P(n) which has been implemented as a Prolog Interpreter. | |||||
BibTeX:
@inproceedings{ki97,
author = {Artosi, Alberto and Cattabriga, Paola and Guido Governatori},
title = {A Modal Computational Framework for Default Reasoning},
booktitle = {Proceedings of KI-97},
publisher = {Springer-Verlag},
year = {1997},
number = {1303},
pages = {373-376}
}
|
|||||
| Billington, D., Antoniou, G., Governatori, G. & Maher, M. J. | Revising Nonmonotonic Belief Sets: The Case of Defeasible Logic | 1999 | KI-99: Advances in Artificial Intelligence | inproceedings | URL |
| Abstract: The revision and transformation of knowledge is widely recognized as a key issue in knowledge representation and reasoning. Reasons for the importance of this topic are the fact that intelligent systems are gradually developed and refined, and that often the environment of an intelligent system is not static but changes over time. Traditionally belief revision has been concerned with revising first order theories. Nonmonotonic reasoning provides rigorous techniques for reasoning with incomplete information. Until recently the dynamics of nonmonotonic reasoning approaches has attracted little attention. This paper studies the dynamics of defeasible logic, a simple and efficient form of nonmonotonic reasoning based on defeasible rules and priorities. We define revision and contraction operators, propose postulates motivated by the form or the intuition of the AGM postulates for classical belief revision, and verify that the operators satisfy the postulates. | |||||
BibTeX:
@inproceedings{ki99,
author = {Billington, David and Antoniou, Grigoris and Governatori, Guido and Maher, Michael J.},
title = {Revising Nonmonotonic Belief Sets: The Case of Defeasible Logic},
booktitle = {KI-99: Advances in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {1999},
number = {1701},
pages = {101-112},
url = {http://www.springer.de/comp/lncs/index.html}
}
|
|||||
| Antoniou, G., Maher, M. J., Billington, D. & Governatori, G. | Comparison of Sceptical NAF-Free Logic Programming Approaches | 1999 | Logic Programming and Non-monotonic Reasoning | inproceedings | URL |
| Abstract: Recently there has been increased interest in logic programming-based default reasoning approaches which are not using negation-as-failure in their object language. Instead, default reasoning is modelled by rules and a priority relation among them. Historically the first logic in this class was Defeasible Logic. In this paper we will study its relationship to other approaches which also rely on the idea of using logic rules and priorities. In particular we will study sceptical LPwNF, courteous logic programs, and priority logic. | |||||
BibTeX:
@inproceedings{lpnmr,
author = {Antoniou, Grigoris and Maher, Michael J. and Billington, David and Governatori, Guido},
title = {Comparison of Sceptical NAF-Free Logic Programming Approaches},
booktitle = {Logic Programming and Non-monotonic Reasoning},
publisher = {Springer-Verlag},
year = {1999},
number = {1730},
pages = {347-356},
url = {http://springerlink.metapress.com/index/XT39RUCLE20BA48F}
}
|
|||||
| Antoniou, G., Billington, D., Governatori, G. & Maher, M. J. | A flexible framework for defeasible logics | 2000 | Proceeding of the 9$^th$ Workshop on Non-Monotonic Reasoning | inproceedings | URL |
| Abstract: Logics for knowledge representation suffer from over-specialization: while each logic may provide an ideal representation formalism for some problems, it is less than optimal for others. A solution to this problem is to choose from several logics and, when necessary, combine the representations. In general, such an approach results in a very difficult problem of combination. However, if we can choose the logics from a uniform framework then the problem of combining them is greatly simplified. In this paper, we develop such a framework for defeasible logics. It supports all defeasible logics that satisfy a strong negation principle. We use logic meta-programs as the basis for the framework. | |||||
BibTeX:
@inproceedings{nmr,
author = {Antoniou, Grigoris and Billington, David and Governatori, Guido and Maher, Michael J.},
title = {A flexible framework for defeasible logics},
booktitle = {Proceeding of the 9$^{th}$ Workshop on Non-Monotonic Reasoning},
year = {2000},
url = {http://arXiv.org/cs.AI/0004013}
}
|
|||||
| Governatori, G. & Luppi, A. | Labelled tableaux for non-normal modal logics | 2000 | AI*IA 99: Advances in Artificial Intelligence | inproceedings | URL |
| Abstract: In this paper we show how to extend a tableau-like proof system for normal modal logic, in order to deal with classes of non-normal modal logics, such as monotonic and regular, in a uniform and modular way. | |||||
BibTeX:
@inproceedings{nn,
author = {Governatori, Guido and Luppi, Alessandro},
title = {Labelled tableaux for non-normal modal logics},
booktitle = {AI*IA 99: Advances in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {2000},
number = {1792},
pages = {119-130},
url = {http://springerlink.metapress.com/index/RJ5T3QVNRW3N4940}
}
|
|||||
| Governatori, G., Maher, M. J., Antoniou, G. & Billington, D. | Argumentation Semantics for Defeasible Logics | 2000 | PRICAI 2000: Topics in Artificial Intelligence | inproceedings | URL |
| Abstract: Defeasible logic is an efficient non-monotonic logic that is defined only proof-theoretically. It has potential application in some legal domains. We present here argumentation semantics for variants of defeasible logic that will be useful in these applications. | |||||
BibTeX:
@inproceedings{pricai2000,
author = {Governatori, Guido and Maher, Michael J. and Antoniou, Grigoris and Billington, David},
title = {Argumentation Semantics for Defeasible Logics},
booktitle = {PRICAI 2000: Topics in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {2000},
number = {1886},
pages = {27-37},
url = {http://www.springer.de/comp/lncs/index.html}
}
|
|||||
| Di Giusto, P. & Governatori, G. | Modifying Is Better Than Deleting: A New Approach To Base Revision | 1999 | AI*IA 99 | inproceedings | |
| Abstract: We present three approaches to belief base revision, which are examined also in the case in which the sentences in the base are partitioned between those which can and those which cannot be changed; the approaches are shown to be semantically equivalent. A new approach is then presented, based on the modification of individual rules, instead of deletion. The resulting base is semantically equivalent to that generated by the other approaches, in the sense that it has the same models, but the rule part alone has less models, that is, is subjected to a smaller change. | |||||
BibTeX:
@inproceedings{revision-ai*ia,
author = {Di Giusto, Paolo and Governatori, Guido},
title = {Modifying Is Better Than Deleting: A New Approach To Base Revision},
booktitle = {AI*IA 99},
publisher = {Pitagora},
year = {1999},
pages = {145-154}
}
|
|||||
| Artosi, A. & Governatori, G. | Modal Tableaux for Nonmonotonic Reasoning | 1998 | Prospettive della logica e della filosofia della scienza | inproceedings | |
| Abstract: The tableau-like proof system KEM has been proven to be able to cope with a wide variety of (normal) modal logics. KEM is based on D'Agostino and Mondadori's (1994) classical proof system KE, a combination of tableau and natural deduction inference rules which allows for a restricted (``analytic'') Use of the cut rule. The key feature of KEM, besides its being based neither on resolution nor on standard sequent/tableau inference techniques, is that it generates models and checks them using a label scheme to bookkeep ``world'' paths. This formalism can be extended to handle various system of multimodal logic devised for dealing with nonmonotonic reasoning, by relying in particular on Meyer and van der Hoek's (1992) logic for actuality and preference. In this paper we shall be concerned with developing a similar extension this time by relying on Schwind and Siegel's (1993,1994) system H, another multimodal logic devised for dealing with nonmonotonic inference. | |||||
BibTeX:
@inproceedings{silfs,
author = {Artosi, Alberto and Governatori, Guido},
title = {Modal Tableaux for Nonmonotonic Reasoning},
booktitle = {Prospettive della logica e della filosofia della scienza},
publisher = {ETS},
year = {1998},
pages = {203-213}
}
|
|||||
| Artosi, A., Governatori, G. & Rotolo, A. | A Labelled Tableau Calculus for Nonmonotonic (Cumulative) Consequence Relations | 2000 | Automated Reasoning with Analytic Tableaux and Related Methods | inproceedings | URL |
| Abstract: In this paper we present a labelled proof method for computing nonmonotonic consequence relations in a conditional logic setting. The method is based on the usual possible world semantics for conditional logic. The label formalism $KEM$, introduced to account for the semantics of normal modal logics, is easily adapted to the semantics of conditional logic by simply indexing labels with formulas. The inference rules are provided by the propositional system $KE^+$ ---a tableau-like analytic proof system devised to be used both as a refutation and a direct method of proof--- enlarged with suitable elimination rules for the conditional connective. The resulting algorithmic framework is able to compute cumulative consequence relations in so far as they can be expressed as conditional implications. | |||||
BibTeX:
@inproceedings{tab2000,
author = {Artosi, Alberto and Governatori, Guido and Antonino Rotolo},
title = {A Labelled Tableau Calculus for Nonmonotonic (Cumulative) Consequence Relations},
booktitle = {Automated Reasoning with Analytic Tableaux and Related Methods},
publisher = {Springer-Verlag},
year = {2000},
number = {1847},
pages = {82-97},
url = {http://www.springer.de/comp/lncs/index.html}
}
|
|||||
| Governatori, G. | Labelled Tableaux for Multi-Modal Logics | 1995 | Theorem Proving with Analytic Tableaux and Related Methods | inproceedings | |
| Abstract: In this paper we present a tableau-like proof system for multi-modal logics based on D'Agostino and Mondadori's classical refutation system $KE$. The proposed system, that we call $KEM$, works for the logics $S5A$ and $S5P_(n)$ which have been devised by Mayer and van der Hoek for formalizing the notions of actuality and preference. We shall also show how $KEM$ works with the normal modal logics $K45, D45$, and $S5$ which are frequently used as bases for epistemic operators -- knowledge, belief, and we shall briefly sketch how to combine knowledge and belief in a multi-agent setting through $KEM$ modularity. | |||||
BibTeX:
@inproceedings{tableau,
author = {Governatori, Guido},
title = {Labelled Tableaux for Multi-Modal Logics},
booktitle = {Theorem Proving with Analytic Tableaux and Related Methods},
publisher = {Springer-Verlag},
year = {1995},
number = {918},
pages = {79-94}
}
|
|||||
| Governatori, G. |
Un modello formale per il ragionamento giuridico [BibTeX] |
1997 | School: CIRFID, University of Bologna | phdthesis | |
BibTeX:
@phdthesis{tesi,
author = {Governatori, Guido},
title = {Un modello formale per il ragionamento giuridico},
school = {CIRFID, University of Bologna},
year = {1997}
}
|
|||||
| Antoniou, G., Billington, D., Governatori, G. & Maher, M. J. | Representation Results for Defeasible Logic | 2001 | ACM Transactions on Computational Logic | article | DOI |
| Abstract: The importance of transformations and normal forms in logic programming, and generally in computer science, is well documented. This paper investigates transformations and normal forms in the context of Defeasible Logic, a simple but efficient formalism for nonmonotonic reasoning based on rules and priorities. The transformations described in this paper have two main benefits: on one hand they can be used as a theoretical tool that leads to a deeper understanding of the formalism, and on the other hand they have been used in the development of an efficient implementation of defeasible logic. | |||||
BibTeX:
@article{tocl,
author = {Antoniou, Grigoris and Billington, David and Governatori, Guido and Maher, Michael J.},
title = {Representation Results for Defeasible Logic},
journal = {ACM Transactions on Computational Logic},
year = {2001},
volume = {2},
number = {2},
pages = {255-287},
doi = {http://dx.doi.org/10.1145/371316.371517}
}
|
|||||
| Padmanabhan, V. N., Governatori, G. & Sattar, A. | Actions Made Explicit in BDI | 2001 | Advances in Artificial Intelligence | inproceedings | URL |
| Abstract: The Belief, Desire, Intention (BDI) architecture is increasingly being used in a wide range of complex applications for agents. Many theories and models exists which support this architecture and the recent version is that of Capability being added as an additional construct. In all these models the concept of action is seen in an endogenous manner. We argue that the Result of an action performed by an agent is extremely important when dealing with composite actions and hence the need for an explicit representation of them. The Capability factor is supported using a RES construct and it is shown how the components of a composite action is supported using these two. Further, we introduce an OPP (opportunity) operator which in alliance with Result and Capability provides a better semantics for practical reasoning in BDI. | |||||
BibTeX:
@inproceedings{vineet1,
author = {Padmanabhan, Vineet Nair and Governatori, Guido and Sattar, Abdul},
title = {Actions Made Explicit in {BDI}},
booktitle = {Advances in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {2001},
number = {2256},
pages = {390-401},
url = {http://springerlink.metapress.com/index/J4MXPKEXF548QH96}
}
|
|||||
| Dumas, M., Governatori, G., ter Hofstede, A. H. & Russel, N. | An Architecture for Assembling Agents that Participate in Alternative Heterogeneous Auctions | 2002 | RIDE-2EC 2002 | inproceedings | DOI |
| Abstract: This paper addresses the issue of developing agents capable of participating in several potentially simultaneous auctions of different kinds (English, First-Price, Vickrey), with the goal of finding the best price for an item on behalf of their users. Specifically, a multi-agent architecture is proposed, in which a manager agent cooperates with several expert agents, each specialised in a specific kind of auction. The expert agents communicate their knowledge to the manager agent in the form of probability functions, capturing the likelihood that a bid of a given price may win an auction. Given a set of such functions, the manager agent builds a bidding plan that it executes in concert with the expert agents. | |||||
BibTeX:
@inproceedings{ride,
author = {Dumas, Marlon and Governatori, Guido and ter Hofstede, Arthur H.M. and Russel, Nick},
title = {An Architecture for Assembling Agents that Participate in Alternative Heterogeneous Auctions},
booktitle = {RIDE-2EC 2002},
publisher = {IEEE Press},
year = {2002},
pages = {75-83},
doi = {http://dx.doi.org/10.1109/RIDE.2002.995101}
}
|
|||||
| Governatori, G. & Rotolo, A. | A Gentzen System for Reasoning with Contrary-To-Duty Obligations. A preliminary Study | 2002 | $eon'02 | inproceedings | |
| Abstract: In this paper we present a Gentzen system for reasoning with contrary-to-duty obligations. The intuition behind the system is that a contrary-to-duty is a special kind of normative exception. The logical machinery to formalize this idea is taken from substructural logics and it is based on the definition of a new non-classical connective capturing the notion of reparational obligation. Then the system is tested against well-known contrary-to-duty paradoxes. | |||||
BibTeX:
@inproceedings{deon2002,
author = {Governatori, Guido and Rotolo, Antonino},
title = {A {G}entzen System for Reasoning with Contrary-To-Duty Obligations. A preliminary Study},
booktitle = {$\Delta$eon'02},
publisher = {Imperial College},
year = {2002},
pages = {97-116}
}
|
|||||
| Dumas, M., Aldred, L., Governatori, G., ter Hofstede, A. H. & Russell, N. | A Probabilistic Approach to Automated Bidding in Alternative Auctions | 2002 | WWW2002 | inproceedings | DOI |
| Abstract: This paper presents an approach to develop bidding agents that participate in multiple alternative auctions, with the goal of obtaining an item at the lowest price. The approach consists of a prediction method and a planning algorithm. The prediction method exploits the history of past auctions in order to build probability functions capturing the belief that a bid of a given price may win a given auction. The planning algorithm computes the lowest price, such that by sequentially bidding in a subset of the relevant auctions, the agent can obtain the item at that price with an acceptable probability. The approach addresses the case where the auctions are for substitutable items with different values. Experimental results are reported, showing that the approach increases the payoff of their users and the welfare of the market | |||||
BibTeX:
@inproceedings{www,
author = {Dumas, Marlon and Aldred, Lachlan and Governatori, Guido and ter Hofstede, Arthur H.M. and Russell, Nick},
title = {A Probabilistic Approach to Automated Bidding in Alternative Auctions},
booktitle = {WWW2002},
publisher = {ACM Press},
year = {2002},
pages = {99-108},
doi = {http://dx.doi.org/10.1145/511446.511460}
}
|
|||||
| Governatori, G., Gelati, J., Rotolo, A. & Sartor, G. | Actions, Institutions, Powers. Preliminary Notes | 2002 | International Workshop on Regulated Agent-Based Social Systems: Theories and Applications (RASTA'02) | inproceedings | |
| Abstract: In this paper we analyse some logical notions relevant for representing the dynamics of institutionalised organisations. In particular, some well-known action concepts introduced in the Kanger-Lindahl-Pörn logical theory of agency are discussed and integrated. Secondly, moving from the work of Jones and Sergot, a logical characterisation is provided of the ideas of institutional links, ``counts-as'' connections, and institutional facts. This approach is then enriched by a new modal operator $proc$, intended to account for the autonomous and decentralised creation of new institutional facts and normative positions within institutions. | |||||
BibTeX:
@inproceedings{rasta02,
author = {Governatori, Guido and Gelati, Jonathan and Rotolo, Antonino and Sartor, Giovanni},
title = {Actions, Institutions, Powers. Preliminary Notes},
booktitle = {International Workshop on Regulated Agent-Based Social Systems: Theories and Applications (RASTA'02)},
publisher = {Fachbereich Informatik, Universit\"at Hamburg},
year = {2002},
volume = {318},
number = {FBI-HH-M-318/02},
pages = {131-147}
}
|
|||||
| Governatori, G., Padmanabhan, V. N. & Sattar, A. | On Fibring Semantics for BDI Logics | 2002 | Jelia 2002 | inproceedings | URL |
| Abstract: This study examines BDI logics in the context of Gabbay's fibring semantics. We show that dovetailing (a special form of fibring) can be adopted as a semantic methodology to combine BDI logics. We develop a set of interaction axioms that can capture static as well as dynamic aspects of the mental states in BDI systems, using Catach's incestual schema $G^a, b, c, d$. Further we exemplify the constraints required on fibring function to capture the semantics of interactions among modalities. The advantages of having a fibred approach is discussed in the final section. | |||||
BibTeX:
@inproceedings{jelia02,
author = {Governatori, Guido and Padmanabhan, Vineet N. and Sattar, Abdul},
title = {On Fibring Semantics for {BDI} Logics},
booktitle = {Jelia 2002},
publisher = {Springer-Verlag},
year = {2002},
number = {2424},
pages = {198-210},
url = {http://springerlink.metapress.com/index/XF6RY52PXMPD1YPJ}
}
|
|||||
| Governatori, G., Padmanabhan, V. N. & Sattar, A. | A Defeasible Logic of Policy-Based Intention (extended abstract) [BibTeX] |
2002 | AI'02 | inproceedings | URL |
BibTeX:
@inproceedings{ai02,
author = {Governatori, Guido and Padmanabhan, Vineet N. and Sattar, Abdul},
title = {A Defeasible Logic of Policy-Based Intention (extended abstract)},
booktitle = {AI'02},
publisher = {Springer-Verlag},
year = {2002},
number = {2557},
pages = {723},
url = {http://springerlink.metapress.com/index/LT1RK1JT7CRYGUL9}
}
|
|||||
| Dumas, M., Governatori, G., ter Hofstede, A. H. M. & Oaks, P. | A Formal Approach to Negotiating Agents Development | 2002 | Electronic Commerce Research and Applications | article | URL |
| Abstract: This paper presents a formal and executable approach to capture the behaviour of parties involved in a negotiation. A party is modeled as a negotiating agent composed of a communication module, a control module, a reasoning module, and a knowledge base. The control module is expressed as a statechart, and the reasoning module as a defeasible logic program. A strategy specification therefore consists of a statechart, a set of defeasible rules, and a set of initial facts. Such a specification can be dynamically plugged into an agent shell incorporating a statechart interpreter and a defeasible logic inference engine, in order to yield an agent capable of participating in a given type of negotiations. The choice of statecharts and defeasible logic with respect to other formalisms is justified against a set of desirable criteria, and their suitability is illustrated through concrete examples of bidding and multi-lateral bargaining scenarios. | |||||
BibTeX:
@article{ecra2002,
author = {Dumas, Marlon and Governatori, Guido and ter Hofstede, Arthur H. M. and Oaks, Phillipa },
title = {A Formal Approach to Negotiating Agents Development},
journal = {Electronic Commerce Research and Applications},
year = {2002},
volume = {1},
number = {2},
pages = {193-207},
url = {http://www.elsevier.com/locate/ecra}
}
|
|||||
| Governatori, G., Padmanabhan, V. N. & Sattar, A. | A Defeasible Logic of Policy-based Intention | 2002 | Australasian Workshop on Computational Logic 2002: Proceedings | inproceedings | |
| Abstract: Most of the theories on formalising intention interpret it as a unary modal operator in Kripkean semantics, which gives it a monotonic look. We argue that policy-based intentions tebratman1 exhibit non-monotonic behaviour which could be captured through a non-monotonic system like defeasible logic. The proposed technique alleviates most of the problems related to logical omniscience. | |||||
BibTeX:
@inproceedings{awcl02,
author = {Governatori, Guido and Padmanabhan, Vineet N. and Sattar, Abdul},
title = {A Defeasible Logic of Policy-based Intention},
booktitle = {Australasian Workshop on Computational Logic 2002: Proceedings},
publisher = {Department of Computer Science, The University of Melbourne},
year = {2002},
number = {TR2002/6},
pages = {9-20}
}
|
|||||
| Johnston, B. & Governatori, G. | An algorithm for the induction of defeasible logic theories from databases | 2003 | Database Technology 2003 | inproceedings | URL |
| Abstract: Defeasible logic is a non-monotonic logic with applications in rule-based domains such as law. To ease the development and improve the accuracy of expert systems based on defeasible logic, it is desirable to automatically induce a theory of the logic from a training set of precedent data. Empirical evidence suggests that minimal theories that describe the training set tend to be more faithful representations of reality. We show via transformation from the hitting set problem that this global minimization problem is intractable, belonging to the class of NP optimisation problems. Given the inherent difficulty of finding the optimal solution, we instead use heuristics and demonstrate that a best-first, greedy, branch and bound algorithm can be used to find good theories in short time. This approach displays significant improvements in both accuracy and theory size as compared to recent work in the area that post-processed the output of an Aprori association rule-mining algorithm, with comparable execution times. | |||||
BibTeX:
@inproceedings{adc03,
author = {Johnston, Benjamin and Governatori, Guido},
title = {An algorithm for the induction of defeasible logic theories from databases},
booktitle = {Database Technology 2003},
publisher = {ACS},
year = {2003},
number = {17},
pages = {75-83},
url = {http://www.jrpit.flinders.edu.au/confpapers/CRPITV17Johnston.pdf}
}
|
|||||
| Gelati, J., Governatori, G., Rotolo, A. & Sartor, G. | Declarative Power, Representation, and Mandate: A Formal Anaysis | 2002 | Legal Knowledge and Information Systems | incollection | URL |
| Abstract: In this paper we provide a formal framework for developing the idea of normative co-ordination. We argue that this idea is based on the assumption that agents can achieve flexible co-ordination by conferring normative positions to other agents. These positions include duties, permissions, and powers. In particular, we introduce the idea of declarative power, which consists in the capacity of the power-holder of creating normative positions, involving other agents, simply by ``proclaiming'' such positions. In addition, we account also for the concepts of representation, consisting in the representative's capacity of acting in the name of his principal, and of mandate, which corresponds the mandatee's duty to act as the mandator has requested. Finally, we show how the above framework can be applied to the contract-net protocol. | |||||
BibTeX:
@incollection{jurix02,
author = {Gelati, Jonathan and Governatori, Guido and Rotolo, Antonino and Sartor, Giovanni},
title = {Declarative Power, Representation, and Mandate: A Formal Anaysis},
booktitle = {Legal Knowledge and Information Systems},
publisher = {IOS Press},
year = {2002},
number = {89},
pages = {41-52},
url = {http://www.jurix.nl/pdf/j02-05.pdf}
}
|
|||||
| Governatori, G. | On the Relative Complexity of Modal Tableaux | 2003 | CATS'03 | inproceedings | URL |
| Abstract: We investigate the relative complexity of two free-variable labelled modal tableaux (KEM and Single Step Tableaux, . We discuss the reasons why p-simulation is not a proper measure of the relative complexity of tableaux-like proof systems, and we propose an improved comparison scale (p-search-simulation). Finally we show that KEM p-search-simulates SST while SST cannot p-search-simulate | |||||
BibTeX:
@inproceedings{cats03,
author = {Governatori, Guido},
title = {On the Relative Complexity of Modal Tableaux},
booktitle = {CATS'03},
publisher = {Elsevier},
year = {2003},
volume = {78},
pages = {36-53},
url = {http://www.elsevier.nl/locate/entcs/volume78.html}
}
|
|||||
| Johnston, B. & Governatori, G. | Induction of Defeasible Logic Theories in the Legal Domain | 2003 | Procedings of the 9th International Conference on Artificial Intelligence and Law | inproceedings | DOI |
| Abstract: The market for intelligent legal information systems remains relatively untapped and while this might be interpreted as an indication that it is simply impossible to produce a system that satisfies the needs of the legal community, an analysis of previous attempts at producing such systems reveals a common set of deficiencies that in-part explain why there have been no overwhelming successes to date. Defeasible logic, a logic with proven successes at representing legal knowledge, seems to overcome many of these deficiencies and is a promising approach to representing legal knowledge. Unfortunately, an immediate application of technology to the challenges in this domain is an expensive and computationally intractable problem. So, in light of the benefits, we seek to find a practical algorithm that uses heuristics to discover an approximate solution. As an outcome of this work, we have developed an algorithm that integrates defeasible logic into a decision support system by automatically deriving its knowledge from databases of precedents. Experiments with the new algorithm are very promising -- delivering results comparable to and exceeding other approaches. | |||||
BibTeX:
@inproceedings{icail03,
author = {Johnston, Benjamin and Governatori, Guido},
title = {Induction of Defeasible Logic Theories in the Legal Domain},
booktitle = {Procedings of the 9th International Conference on Artificial Intelligence and Law},
publisher = {ACM Press},
year = {2003},
pages = {204-213},
doi = {http://dx.doi.org/10.1145/1047788.1047834}
}
|
|||||
| Governatori, G. & Rotolo, A. | A Defeasible Logic of Institutional Agency | 2003 | NRAC'03 | inproceedings | |
| Abstract: A non-monotonic logic of institutional agency is defined combining a computationally oriented non-monotonic system (Defeasible Logic) and intensional notions of agency. | |||||
BibTeX:
@inproceedings{nrac03,
author = {Governatori, Guido and Rotolo, Antonino},
title = {A Defeasible Logic of Institutional Agency},
booktitle = {NRAC'03},
year = {2003},
pages = {97-104}
}
|
|||||
| Governatori, G., Maher, M. J., Billington, D. & Antoniou, G. | Argumentation Semantics for Defeasible Logics | 2004 | Journal of Logic and Computation | article | DOI |
| Abstract: Defeasible reasoning is a simple but efficient rule-based approach to nonmonotonic reasoning. It has powerful implementations and shows promise to be applied in the areas of legal reasoning and the modeling of business rules. This paper establishes significant links between defeasible reasoning and argumentation. In particular, Dung-like argumentation semantics is provided for two key defeasible logics, of which one is ambiguity propagating and the other ambiguity blocking. There are several reasons for the significance of this work: (a) establishing links between formal systems leads to a better understanding and cross-fertilization, in particular our work sheds light on the argumentation-theoretic features of defeasible logic; (b) we provide the first ambiguity blocking Dung-like argumentation system; (c) defeasible reasoning may provide an efficient implementation platform for systems of argumentation; and (d) argumentation-based semantics support a deeper understanding of defeasible reasoning, especially in the context of the intended applications. | |||||
BibTeX:
@article{jlc:argumentation,
author = {Governatori, Guido and Maher, Michael J. and Billington, David and Antoniou, Grigoris},
title = {Argumentation Semantics for Defeasible Logics},
journal = {Journal of Logic and Computation},
year = {2004},
volume = {14},
number = {5},
pages = {675-702},
doi = {http://dx.doi.org/10.1093/logcom/14.5.675}
}
|
|||||
| Dumas, M., Aldred, L., Governatori, G. & ter Hofstede, A. H. | Probabilistic Automated Bidding in Multiple Auctions | 2005 | Journal of Electronic Commerce Research | article | DOI |
| Abstract: This paper presents an approach to develop bidding agents that participate in multiple alternative auctions, with the goal of obtaining an item with a given probability. The approach consists of a prediction method and a planning algorithm. The prediction method exploits the history of past auctions in order to build probability functions capturing the belief that a bid of a given price may win a given auction. The planning algorithm computes a price, such that by sequentially bidding in a subset of the relevant auctions, the agent can obtain the item at that price with the desired probability. The approach addresses the case where the auctions are for substitutive items with different values. Experimental results show that the approach increases the payoff of their users and the welfare of the market. | |||||
BibTeX:
@article{jecr,
author = {Dumas, Marlon and Aldred, Lachlan and Governatori, Guido and ter Hofstede, Arthur H.M.},
title = {Probabilistic Automated Bidding in Multiple Auctions},
journal = {Journal of Electronic Commerce Research},
publisher = {Springer Science+Business Media B.V.,},
year = {2005},
volume = {5},
number = {1},
pages = {23-47},
doi = {http://dx.doi.org/10.1023/B:ELEC.0000045972.75533.90}
}
|
|||||
| Governatori, G. & Padmanabhan, V. | A Defeasible Logic of Policy-based Intention | 2003 | AI 2003: Advances in Artificial Intelligence | inproceedings | URL |
| Abstract: Most of the theories on formalising intention interpret it as a unary modal operator in Kripkean semantics, which gives it a monotonic look. We argue that policy-based intentions tebratman1 exhibit non-monotonic behaviour which could be captured through a non-monotonic system like defeasible logic. To this end we outline a defeasible logic of intention. The proposed technique alleviates most of the problems related to logical omniscience. The proof theory given shows how our approach helps in the maintenance of intention-consistency in agent systems like BDI. | |||||
BibTeX:
@inproceedings{ai03v,
author = {Governatori, Guido and Padmanabhan, Vineet},
title = {A Defeasible Logic of Policy-based Intention},
booktitle = {AI 2003: Advances in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {2003},
number = {2903},
pages = {414-426},
url = {http://springerlink.metapress.com/index/G9M5YK3UVDCY0JBB}
}
|
|||||
| Governatori, G., Lomuscio, A. & Sergot, M. | A Tableaux System for Deontic Interpreted Systems | 2003 | AI 2003: Advances in Artificial Intelligence | inproceedings | URL |
| Abstract: We develop a labelled tableaux system for the modal logic $KD45^i-j_n$ extended with epistemic notions. This logic characterises a particular type of interpreted systems used to represent and reason about states of correct and incorrect functioning behaviour of the agents in a system, and of the system as a whole. The resulting tableaux system provides a simple decision procedure for the logic. We discuss these issues and we illustrate them with the help of simple examples | |||||
BibTeX:
@inproceedings{ai03gls,
author = {Governatori, Guido and Lomuscio, Alessio and Sergot, Marek},
title = {A Tableaux System for Deontic Interpreted Systems},
booktitle = {AI 2003: Advances in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {2003},
number = {2903},
pages = {339-351},
url = {http://springerlink.metapress.com/index/T4TV93CGJ3VG18TK}
}
|
|||||
| Chow, P. Y. & Governatori, G. | Representing and Reasoning on XForms Document | 2004 | Database Technology 2004 | inproceedings | URL |
| Abstract: Forms are the most common way to interface users and Web-based applications. Traditional forms cannot provide the functionality needed to fulfil the requirements of complex applications. As such, there is a need for a more advanced format of forms to support Web-based application. We argued that XForms easily fit into this criterion of forms. In addition, we observed that there is a need for a tool to reason about the forms with respect to user needs and application requirements. We propose to use Description Logic ALCQI to reason about forms generated by XForms. | |||||
BibTeX:
@inproceedings{adc04cg,
author = {Chow, Peng Yew and Governatori, Guido},
title = {Representing and Reasoning on {XF}orms Document},
booktitle = {Database Technology 2004},
publisher = {ACS},
year = {2004},
number = {27},
pages = {141-150},
url = {http://crpit.com/confpapers/CRPITV27Cheow.pdf}
}
|
|||||
| Governatori, G., Rotolo, A. & Sadiq, S. | A Model of Dynamic Resource Allocation in Workflow Systems | 2004 | Database Technology 2004 | inproceedings | URL |
| Abstract: Current collaborative work environments are characterized by dynamically changing organizational structures. Although there have been several efforts to refine work distribution, especially in workflow management, most literature assumes a static database approach which captures organizational roles, groups and hierarchies and implements a dynamic roles based agent assignment protocol. However, in practice only partial information may be available for organizational models, and in turn a large number of exceptions may emerge at the time of work assignment. In this paper we present an organizational model based on a policy based normative system. The model is based on a combination of an intensional logic of agency and a flexible, but computationally feasible, non-monotonic formalism (Defeasible Logic). Although this paper focuses on the model specification, the proposed approach to modelling agent societies provides a means of reasoning with partial and unpredictable information as is typical of organizational agents in workflow systems. | |||||
BibTeX:
@inproceedings{adc04grs,
author = {Governatori, Guido and Rotolo, Antonino and Sadiq, Shazia},
title = {A Model of Dynamic Resource Allocation in Workflow Systems},
booktitle = {Database Technology 2004},
publisher = {ACS},
year = {2004},
number = {27},
pages = {197-206},
url = {http://crpit.com/confpapers/CRPITV27Governatori.pdf}
}
|
|||||
| Governatori, G. & Rotolo, A. | A Computational Framework for Non-Monotonic Agency, Institutionalised Power and Multi-Agent Systems | 2003 | Legal Knowledge and Information Systems | inproceedings | URL |
| Abstract: This work provides a first computational framework to capture some of the theoretical intuitions developed by the present authors and other colleagues. More precisely, in this paper we propose a computationally oriented model of institutional agency based on Defeasible Logic. The focus here is on the notions of counts-as link and on those of attempt and of personal and direct action to realise states of affairs. | |||||
BibTeX:
@inproceedings{jurix03,
author = {Governatori, Guido and Rotolo, Antonino},
title = {A Computational Framework for Non-Monotonic Agency, Institutionalised Power and Multi-Agent Systems},
booktitle = {Legal Knowledge and Information Systems},
publisher = {IOS Press},
year = {2003},
number = {106},
pages = {151-152},
url = {http://www.jurix.nl/pdf/j03-20.pdf}
}
|
|||||
| Governatori, G. & Rotolo, A. | Defeasible Logic: Agency, Intention and Obligation | 2004 | Deontic Logic in Computer Science | inproceedings | URL |
| Abstract: We propose a computationally oriented non-monotonic multi-modal logic arising from the combination of agency, intention and obligation. We argue about the defeasible nature of these notions and then we show how to represent and reason with them in the setting of defeasible logic. | |||||
BibTeX:
@inproceedings{deon:04,
author = {Governatori, Guido and Rotolo, Antonino},
title = {Defeasible Logic: Agency, Intention and Obligation},
booktitle = {Deontic Logic in Computer Science},
publisher = {Springer},
year = {2004},
number = {3065},
pages = {114-128},
url = {http://springerlink.metapress.com/index/NN0UCU6140VV1HVL}
}
|
|||||
| Gelati, J., Governatori, G., Rotolo, A. & Sartor, G. | Normative Autonomy and Normative Co-ordination: Declarative Power, Representation, and Mandate | 2004 | Artificial Intelligence and Law | article | DOI |
| Abstract: In this paper we provide a formal analysis of the idea of normative co-ordination. We argue that this idea is based on the assumption that agents can achieve flexible co-ordination by conferring normative positions to other agents. These positions include duties, permissions, and powers. In particular, we explain the idea of declarative power, which consists in the capacity of the power-holder of creating normative positions, involving other agents, simply by ``proclaiming'' such positions. In addition, we account also for the concepts of representation, namely the representative's capacity of acting in the name of his principal, and of mandate, which is the mandatee's duty to act as the mandator has requested. Finally, we show how the framework can be applied to represent the contract-net protocol. Some brief remarks on future research and applications conclude this contribution. | |||||
BibTeX:
@article{GelGovRotSar:AIL:04:Normative,
author = {Gelati, Jonathan and Governatori, Guido and Rotolo, Antonino and Sartor, Giovanni},
title = {Normative Autonomy and Normative Co-ordination: Declarative Power, Representation, and Mandate},
journal = {Artificial Intelligence and Law},
year = {2004},
volume = {12},
number = {1-2},
pages = {53-81},
doi = {http://dx.doi.org/10.1007/s10506-004-2807-0}
}
|
|||||
| Governatori, G. & Rotolo, A. | On the Axiomatization of Elgesem's Logic of Agency | 2004 | AiML 2004 -- Advances in Modal Logic | inproceedings | URL |
| Abstract: In this paper we show that the Hilbert system of agency and ability presented by Dag Elgesem is incomplete with respect to the intended semantics. We argue that completeness result may be easily regained. Finally, we shortly discuss some issues related to the philosophical intuition behind his approach. This is done by examining Elgesem's modal logic of agency and ability using semantics with different flavours. | |||||
BibTeX:
@inproceedings{GovRot:04:AIML,
author = {Governatori, Guido and Rotolo, Antonino},
title = {On the Axiomatization of Elgesem's Logic of Agency},
booktitle = {AiML 2004 -- Advances in Modal Logic},
publisher = {Department of Computer Science, University of Manchester},
year = {2004},
number = {UMCS-04-9-1},
pages = {130-144},
url = {http://www.cs.man.ac.uk/cstechrep/index.html}
}
|
|||||
| Song, I., Governatori, G. & Colomb, R. | An Interaction Model for Affect Monitoring | 2004 | Advances in Artificial Intelligence | inproceedings | DOI |
| Abstract: This paper investigates how we can precisely define what process designers are ought achieve for what they have promised and more importantly in a way that satisfies human users. Toward these goals, an interaction model for processes and an Affect Monitoring Framework (AMF) are proposed based on our analysis on speech act theory and cognitive-based emotion models. The Affect Monitoring Framework is to detect and predict negative affects on users and to resolve caused or predicted causes of negative affects automatically. | |||||
BibTeX:
@inproceedings{ai04,
author = {Song, Insu and Governatori, Guido and Colomb, Robert},
title = {An Interaction Model for Affect Monitoring},
booktitle = {Advances in Artificial Intelligence},
publisher = {Springer-Verlag},
year = {2004},
number = {3339},
pages = {979-984},
doi = {http://dx.doi.org/10.1007/b104336}
}
|
|||||
| Governatori, G. | Defeasible Description Logic | 2004 | Rules and Rule Markup Languages for the Semantic Web: Third International Workshop, RuleML 2004 | inproceedings | DOI |
| Abstract: We propose to extend description logic with defeasible rules, and to use the inferential mechanism of defeasible logic to reason with description logic constructors. | |||||
BibTeX:
@inproceedings{ruleml04,
author = {Governatori, Guido},
title = {Defeasible Description Logic},
booktitle = {Rules and Rule Markup Languages for the Semantic Web: Third International Workshop, RuleML 2004},
publisher = {Springer-Verlag},
year = {2004},
number = {3323},
pages = {98-112},
doi = {http://dx.doi.org/10.1007/b102922}
}
|
|||||
| Governatori, G. & Rotolo, A. | On the Axiomatization of Elgesem's Logic of Agency and Ability | 2005 | Journal of Philosophical Logic | article | DOI |
| Abstract: In this paper we show that the Hilbert system of agency and ability presented by Dag Elgesem is incomplete with respect to the intended semantics. We argue that completeness result may be easily regained. Finally, we shortly discuss some issues related to the philosophical intuition behind his approach. This is done by examining Elgesem's modal logic of agency and ability using semantics with different flavours. | |||||
BibTeX:
@article{elgesem:JPL,
author = {Governatori, Guido and Rotolo, Antonino},
title = {On the Axiomatization of Elgesem's Logic of Agency and Ability},
journal = {Journal of Philosophical Logic},
year = {2005},
volume = {34},
number = {4},
pages = {403-431},
doi = {http://dx.doi.org/10.1007/s10992-004-6368-1}
}
|
|||||
| Governatori, G. & Rotolo, A. | Representing Contracts Using RuleML | 2004 | Legal Knowledge and Information Systems | inproceedings | URL |
| Abstract: This paper presents an approach for the specification and implementation of e-contracts for Web monitoring. This is done in the setting of RuleML. We argue that monitoring contract execution requires also a logical account of deontic concepts and of violations. Accordingly, RuleML is extended to cover these aspects. | |||||
BibTeX:
@inproceedings{jurix04,
author = {Governatori, Guido and Rotolo, Antonino},
title = {Representing Contracts Using {RuleML}},
booktitle = {Legal Knowledge and Information Systems},
publisher = {IOS Press},
year = {2004},
number = {120},
pages = {141-150},
url = {http://www.jurix.nl/pdf/j04-16.pdf}
}
|
|||||
| Governatori, G. | Representing Business Contracts in RuleML | 2005 | International Journal of Cooperative Information Systems | article | DOI |
| Abstract: This paper presents an approach for the specification and implementation of translating contracts from a human-oriented form into an executable representation for monitoring. This will be done in the setting of The task of monitoring contract execution and performance requires a logical account of deontic and defeasible aspects of legal language; currently such aspects are not covered by accordingly we show how to extend it to cover such notions. From its logical form, the contract will be thus transformed into a machine readable rule notation and eventually implemented as executable semantics via any mark-up languages depending on the client's preference, for contract monitoring purposes. | |||||
BibTeX:
@article{coala,
author = {Governatori, Guido},
title = {Representing Business Contracts in {RuleML}},
journal = {International Journal of Cooperative Information Systems},
year = {2005},
volume = {14},
number = {2-3},
pages = {181-216},
doi = {http://dx.doi.org/10.1142/S0218843005001092}
}
|
|||||
| Governatori, G., Rotolo, A. & Sartor, G. | Temporalised Normative Positions in Defeasible Logic | 2005 | 10th International Conference on Artificial Intelligence and Law (ICAIL05) | inproceedings | DOI |
| Abstract: We propose a computationally oriented non-monotonic multi-modal logic arising from the combination of temporalised agency and temporalised normative positions. We argue about the defeasible nature of these notions and then we show how to represent and reason with them in the setting of Defeasible Logic. | |||||
BibTeX:
@inproceedings{icail05,
author = {Governatori, Guido and Rotolo, Antonino and Sartor, Giovanni},
title = {Temporalised Normative Positions in Defeasible Logic},
booktitle = {10th International Conference on Artificial Intelligence and Law (ICAIL05)},
publisher = {ACM Press},
year = {2005},
pages = {25-34},
doi = {http://dx.doi.org/10.1145/1165485.1165490}
}
|
|||||
| Governatori, G. & Milosevic, Z. | Dealing with contract violations: formalism and domain specific language | 2005 | 9th International Enterprise Distributed Object Computing Conference (EDOC 2005) | inproceedings | DOI |
| Abstract: This paper presents a formal system for reasoning about violations of obligations in contracts. The system is based on the formalism for the representation of contrary-to-duty obligations. These are the obligations that take place when other obligations are violated as typically applied to penalties in contracts. The paper shows how this formalism can be mapped onto the key policy concepts of a contract specification language. This language, called Business Contract Language (BCL) was previously developed to express contract conditions of relevance for run time contract monitoring. The aim of this mapping is to establish a formal underpinning for this key subset of BCL. | |||||
BibTeX:
@inproceedings{edoc2005,
author = {Governatori, Guido and Milosevic, Zoran},
title = {Dealing with contract violations: formalism and domain specific language},
booktitle = {9th International Enterprise Distributed Object Computing Conference (EDOC 2005)},
publisher = {IEEE Computer Society},
year = {2005},
pages = {46-57},
doi = {http://dx.doi.org/10.1109/EDOC.2005.13}
}
|
|||||
| Governatori, G. & Milosevic, Z. | An Approach for Validating BCL Contract Specifications | 2005 | 2nd EDOC Workshop on Contract Architectures and Languages (CoALA 2005) | inproceedings | |
| Abstract: We continue the study, started in [5], on the formal relationships between a domain specific contract language (BCL) and the logic of violation (FCL) proposed in [6,7]. We discuss the use of logical methods for the representation and analysis of business contracts. The proposed analysis is based on the notions of normal and canonical forms of contracts expressed in FCL. Finally we present a mapping from FCL to BCL that can be used to provide an executable model of a formal representation of a contract. | |||||
BibTeX:
@inproceedings{GovMil:Coala05:Approach,
author = {Governatori, Guido and Milosevic, Zoran},
title = {An Approach for Validating BCL Contract Specifications},
booktitle = {2nd EDOC Workshop on Contract Architectures and Languages (CoALA 2005)},
publisher = {IEEE Digital Library},
year = {2005},
note = {Published on CD}
}
|
|||||
| Governatori, G. & Hoang, D. P. | DR-CONTRACT: An Architecture for e-Contracts in Defeasible Logic | 2005 | 2nd EDOC Workshop on Contract Architectures and Languages (CoALA 2005) | inproceedings | |
| Abstract: In this paper we present an architecture to represent and reason on e-Contracts based on the DR-device architecture supplemented with a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe e-contracts for a monitoring perspective in Defeasible Logic. | |||||
BibTeX:
@inproceedings{coala05,
author = {Governatori, Guido and Hoang, Duy Pham},
title = {DR-CONTRACT: An Architecture for e-Contracts in Defeasible Logic},
booktitle = {2nd EDOC Workshop on Contract Architectures and Languages (CoALA 2005)},
publisher = {IEEE Digital Library},
year = {2005},
note = {Published on CD}
}
|
|||||
| Dastani, M., Governatori, G., Rotolo, A. & van der Torre, L. | Preferences of Agents in Defeasible Logic | 2005 | AI 2005: Advances in Artificial Intelligence, 18th Australian Joint Conference on Artificial Intelligence | inproceedings | DOI |
| Abstract: We are interested in programming languages for cognitive agents with preferences. We define rule-based agent theories and inference procedures in defeasible logic, and in this setting we discuss patterns of agent behavior called agent types. | |||||
BibTeX:
@inproceedings{ai05,
author = {Dastani, Mehdi and Governatori, Guido and Rotolo, Antonino and van der Torre, Leendert},
title = {Preferences of Agents in Defeasible Logic},
booktitle = {AI 2005: Advances in Artificial Intelligence, 18th Australian Joint Conference on Artificial Intelligence},
publisher = {Springer},
year = {2005},
volume = {3809},
pages = {695-704},
doi = {http://dx.doi.org/10.1007/11589990_72}
}
|
|||||
| Dastani, M., Governatori, G., Rotolo, A. & van der Torre, L. | Programming Cognitive Agents in Defeasible Logic | 2005 | Logic for Programming, Artificial Intelligence, and Reasoning, 12th International Conference | inproceedings | DOI |
| Abstract: Defeasible Logic is extended to programming languages for cognitive agents with preferences and actions for planning. We define rule-based agent theories that contain preferences and actions, together with inference procedures. We discuss patterns of agent types in this setting. Finally, we illustrate the language by an example of an agent reasoning about web-services. | |||||
BibTeX:
@inproceedings{lpar05,
author = {Dastani, Mehdi and Governatori, Guido and Rotolo, Antonino and van der Torre, Leendert},
title = {Programming Cognitive Agents in Defeasible Logic},
booktitle = {Logic for Programming, Artificial Intelligence, and Reasoning, 12th International Conference},
publisher = {Springer},
year = {2005},
volume = {3835},
pages = {621-636},
doi = {http://dx.doi.org/10.1007/11591191_43}
}
|
|||||
| Su, K., Sattar, A., Wang, K., Luo, X., Governatori, G. & Padmanabhan, V. | Observation-based Model for BDI-Agents | 2005 | AAAI 2005 | inproceedings | |
| Abstract: W | |||||