Dr Odinaldo Rodrigues

Welcome to my web page

I am a member of the Reasoning and Planing Group in the Department of Informatics at King's College London.

My research concentrates mainly in the area of Artificial Intelligence, more specifically in the formalisation of the common-sense reasoning, non-monotonic reasoning, and numerical aspects of argumentation.

For further information about my academic activities at King's, some references to my research work and how to get in touch with me, please use the links on the menu.

Thank you for your visit!

Research interests

My research interests currently revolve around aspects related to Artificial Intelligence, especially in all aspects of the formalisation of common-sense reasoning. These include belief revision, abduction, argumentation theory, machine learning, probabilistic reasoning and non-monotonic reasoning in general.

I work both with the theoretical aspects AI, e.g., foundations of AI, translations between logical systems, belief revision in non-classical logics, merging of argumentation systems, as well as with the application of AI in computer science, including optmisation techniques for requirements engineering, implementation of non-monotonic reasoning systems, BDI systems, concept classification, computation of semantics of argumentation systems, and the like.

The main areas of research interest are summarised below:

Artificial Intelligence

  • Knowledge representation
  • Numerical methods of reasoning
  • Agent systems
  • BDI reasoning
  • Optimisation, searching, etc

Formalisation of the common-sense reasoning

  • Non-monotonic reasoning
  • Belief revision
  • Database updates
  • Argumentation theory
  • Voting problems and preference aggregation
  • Abduction

Recent PC membership

2020

2019

2018

2017

2016

2015

2014

2011

2010

Other activities

Teaching

I have taught several modules at BSc and MSc level including:

  • Elementary Logic with Applications (2012-2017)
  • Artificial Intelligence (2002 and 2009-2016)
  • Computer Science Logic (2008 and 2009)
  • Distributed Systems (2006 and 2007)
  • Internet Systems (2005 and 2006)
  • Conceptual Analysis (2003 and 2004)
  • Database Systems (1999 to 2002)
  • Computational Logic (2001)
  • Data Structures and their Implementation in C++ (1999 and 2000)
  • Logic and Prolog (1998 and 1999)

Current modules

  • Elementary Logic with Applications
  • programming Language Design Paradigms

Selected Publications

Matching entries: 0
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YearDetailsURL/PDF
Hao, Q., Keppens, J. and Rodrigues, O., An Entity-Based Algorithm for Multiple-Relation Extraction from Single Sentences, To appear.

[Abstract] [BibTeX]
Abstract: A substantial amount of expert Biomedical (and other) knowledge is accumulated in the form of natural language texts, such as peer reviewed journal articles and conference abstracts. Often, such texts establish, substantiate, confirm, question or undermine associations or relationships between entities that are useful for a broad range of applications. Currently, the knowledge contained within a corpus of Biomedical texts is rarely extracted and analysed in a systematic manner, because it is extremely time consuming for humans to do so. Efficient techniques to automatically extract such knowledge would facilitate the development of novel applications that systematically review and reuse the knowledge contained in natural language texts. While such techniques are emerging, they often fail to tackle complex sentence structures properly. They often misinterpret them; fail to recognize embedded relationships; struggle with pronoun references; or have difficulty distinguishing the assertion of a relationship from a conjecture about its existence. In this paper, we present a new entity-based algorithm for multiple-relation extraction from unstructured text obtained in electronic form. The contribution of this paper is threefold. First, our algorithm is able to recognize pronoun references and extract the correct bio-entities they refer to. Second, our algorithm can deal with complex sentence structures. Third, we propose a novel approach to determine whether an extracted relationship should be recorded based on the novel concept of relationship polarity. Our approach offers clear performance advantages over conventional verb-based extraction techniques, achieving a precision of extraction of 91.4% and recall of 94% based on the F-measure over a random sample of sentences from the biomedical literature. The algorithms can also be employed in other knowledge domains by changing the database used to identify entities and verbs of interest.
BibTeX: 
@article{hao-et-al:18,
  author = {Q. Hao and J. Keppens and O. Rodrigues},
  title = {An Entity-Based Algorithm for Multiple-Relation Extraction from Single Sentences},
  booktitle = {To appear}
}
Rodrigues, O., SCC-recursive algorithms with conflict detection for decision and enumeration problems in abstract argumentation, To appear.

[Abstract] [BibTeX]
Abstract: In this paper, we provide algorithms for the computation of solutions to several enumeration and decision problems in abstract argumentation theory. The algorithms use the well known SCC-recursive schema of Baroni, Giacomin and Guida, and offer significant performance advantages especially in argumentation frameworks with a complex structure. In addition, we offer a number of optimisations that allow early termination in problems involving the decision of acceptance of arguments under the grounded, complete, preferred and stable semantics. Our approach paves the way for a new class of argumentation algorithms that use conflict detection and learning to prune the search space of solutions.
BibTeX: 
@article{rodrigues-scc:18,
  author = {O. Rodrigues},
  title = {SCC-recursive algorithms with conflict detection for decision and enumeration problems in abstract argumentation},
  booktitle = {To appear}
}
2019 Rodrigues, O., Representing and Comparing Large Sets of Extensions of Abstract Argumentation Frameworks, Proceedings of the 34th ACM/SIGAPP Symposium on Applied Computing (SAC'19), DOI: 10.1145/3297280.3297394, 2019.

[Abstract] [BibTeX]

 URL PDF
Abstract: In argumentation theory, some reasoning problems involve the enu-
meration of all extensions of an abstract argumentation framework.
Abstractly speaking, extensions are simply subsets of a given do-
main having some special properties. The result of the enumeration
is usually presented as a single text file with elements and sets sepa-
rated by designated delimiters. Neither the elements within each set
(a single extension), nor the extensions themselves are presented in
any pre-defined order. Events such as the International Competition
of Computational Models of Argumentation require the compar-
ison of a large number of enumerations and thus performing the
comparisons very efficiently has become very desirable. This paper
presents and compares three different alternative representations
of extensions, one of which is novel for the argumentation domain,
and provides an empirical evaluation of their effectiveness in the
comparison of large enumerations. We found that the newly pro-
posed representation can perform the comparisons in a much more
memory and time efficient manner than existing solutions.
BibTeX: 
@inproceedings{rodrigues-mpz:19,
  author = {O. Rodrigues},
  title = {Representing and Comparing Large Sets of Extensions of Abstract Argumentation Frameworks},
  booktitle = {Proceedings of the 34th ACM/SIGAPP Symposium on Applied Computing (SAC'19)},
  year = {2019},
  doi = {https://doi.org/10.1145/3297280.3297394}
}
2018 Rodrigues, O., EqArgSolver - System Description, Proceedings of the 4th Intl. Conference on Theory and Applications of Formal Argumentation, pp. 150-158, DOI: 10.1007/978-3-319-75553-3_11, 2018.

[BibTeX]

 URL PDF
BibTeX: 
@inproceedings{eqargsolver:17,
  author = {Odinaldo Rodrigues},
  title = {EqArgSolver - System Description},
  booktitle = {Proceedings of the 4th Intl. Conference on Theory and Applications of Formal Argumentation},
  year = {2018},
  pages = {150-158},
  doi = {https://doi.org/10.1007/978-3-319-75553-3_11}
}
2018 Rodrigues, O., A Forward Propagation Algorithm for the Computation of the Semantics of Argumentation Frameworks, Theory and Applications of Formal Argumentation, pp. 120-136, DOI: 10.1007/978-3-319-75553-3_8, 2018.

[BibTeX]

 URL PDF
BibTeX: 
@incollection{Rodrigues_2018,
  author = {Odinaldo Rodrigues},
  title = {A Forward Propagation Algorithm for the Computation of the Semantics of Argumentation Frameworks},
  booktitle = {Theory and Applications of Formal Argumentation},
  publisher = {Springer International Publishing},
  year = {2018},
  pages = {120--136},
  doi = {https://doi.org/10.1007/978-3-319-75553-3_8}
}
2018 Rodrigues, O., An Investigation into Reduction and Direct Approaches to the Computation of Argumentation Semantics, Logic, Intelligence and Artifices: Tributes to Tarcision H. C. Pequeno, pp. 97-120, 2018.

[Abstract] [BibTeX]

  PDF
Abstract: This paper compares the performance of the forward propagation algorithm proposed in [15] (which is used in the solver EqArgSolver) with two custom-built SAT-based argumentation solvers in the search for preferred extensions of abstract argumentation frameworks. The SAT-based solvers employ standard ways of computing argumentation semantics via the characterisation of the concept of extensions as models of propositional logic theories. As a result, the comparisons offer new insights about the employment and combination of reduction and direct approaches to the computation of argumentation semantics.
BibTeX: 
@incollection{rodrigues-RD:17,
  author = {O. Rodrigues},
  title = {An Investigation into Reduction and Direct Approaches to the Computation of Argumentation Semantics},
  booktitle = {Logic, Intelligence and Artifices: Tributes to Tarcision H. C. Pequeno},
  publisher = {College Publications},
  year = {2018},
  pages = {97-120}
}
2018 Young, A.P., Modgil, S. and Rodrigues, O., On the Interaction between Logic and Preference in Structured Argumentation, Theory and Applications of Formal Argumentation, pp. 35-50, DOI: 10.1007/978-3-319-75553-3_3, 2018.

[BibTeX]

 URL PDF
BibTeX: 
@inproceedings{young-et-al-tafa:17,
  author = {Anthony P. Young and Sanjay Modgil and Odinaldo Rodrigues},
  title = {On the Interaction between Logic and Preference in Structured Argumentation},
  booktitle = {Theory and Applications of Formal Argumentation},
  publisher = {Springer International Publishing},
  year = {2018},
  pages = {35--50},
  doi = {https://doi.org/10.1007/978-3-319-75553-3_3}
}
2017 Hao, Q., Keppens, J. and Rodrigues, O., A Verb-based Algorithm for Multiple-Relation Extraction from Single Sentences, Proceedings of the 16th International Conference on Information and Knowledge Engineering, 2017.

[Abstract] [BibTeX]

  PDF
Abstract: With the growing number of unstructured articles written in natural-language, automated extraction of knowledge, such as associations between entities, is becoming essential for many applications. In this paper, we develop an automated verb-based algorithm for multiple relation extraction from unstructured data obtained on-line. Named Entity Recognition (NER) techniques were applied to extract biomedical entities and relations were recognized by algorithms with Natural Language Processing (NLP) techniques. Evaluation based on F-measure with a random sample of sentences from biomedical literature results an average precision of 90% and recall of 82%. We also compared the performance of the proposed algorithm with a single-relation extraction algorithm, indicating improvements of this work. In conclusion, the preliminary study indicates that this method for multiple-relation extraction from unstructured literature is effective. With different training dataset, the algorithm can be applied to different domains. The automated method can be applied to detect and predict hidden relationships among varying areas.
BibTeX: 
@inproceedings{hao-et-al:17,
  author = {Qi Hao and Jeroen Keppens and Odinaldo Rodrigues},
  title = {A Verb-based Algorithm for Multiple-Relation Extraction from Single Sentences},
  booktitle = {Proceedings of the 16th International Conference on Information and Knowledge Engineering},
  year = {2017},
  url = {https://csce.ucmss.com/cr/books/2017/LFS/CSREA2017/IKE3227.pdf}
}
2016 Gabbay, D.M. and Rodrigues, O., Introducing Bayesian Argumentation Networks, The IfColog Journal of Logics and their Applications, Vol. 3 (2), pp. 241-278, 2016.

[BibTeX]

  PDF
BibTeX: 
@article{bayes-argum-network:16,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {Introducing Bayesian Argumentation Networks},
  journal = {The IfColog Journal of Logics and their Applications},
  publisher = {College Publications},
  year = {2016},
  volume = {3},
  number = {2},
  pages = {241-278}
}
2016 Gabbay, D. and Rodrigues, O., Degrees of “in”, “out” and “undecided” in Argumentation Networks, Vol. 287, Frontiers in Artificial Intelligence and Applications, pp. 319-326, DOI: 10.3233/978-1-61499-686-6-319, 2016.

[BibTeX]

 URL PDF
BibTeX: 
@inproceedings{gabbay-rodrigues:16c,
  author = {D. Gabbay and O. Rodrigues},
  title = {Degrees of “in”, “out” and “undecided” in Argumentation Networks},
  booktitle = {Frontiers in Artificial Intelligence and Applications},
  year = {2016},
  volume = {287},
  pages = {319-326},
  doi = {https://doi.org/10.3233/978-1-61499-686-6-319}
}
2016 Gabbay, D.M. and Rodrigues, O., Further Applications of the Gabbay-Rodrigues Iteration Schema in Argumentation and Revision Theories, Vol. 29, Computational Models of Rationality, pp. 392-407, 2016.

[BibTeX]

  PDF
BibTeX: 
@incollection{gabbay-rodrigues-GKI:16,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {Further Applications of the Gabbay-Rodrigues Iteration Schema in Argumentation and Revision Theories},
  booktitle = {Computational Models of Rationality},
  publisher = {College Publications},
  year = {2016},
  volume = {29},
  pages = {392-407}
}
2016 Hosseini, S.A., Modgil, S. and Rodrigues, O., Estimating Second-Order Arguments in Dialogical Settings, Proceedings of the 2016 International Conference on Autonomous Agents and Multiagents Systems, pp. 1469-1470, 2016.

[BibTeX]

  PDF
BibTeX: 
@inproceedings{hosseini-modgil-rodrigues:16,
  author = {S. A. Hosseini and S. Modgil and O. Rodrigues},
  title = {Estimating Second-Order Arguments in Dialogical Settings},
  booktitle = {Proceedings of the 2016 International Conference on Autonomous Agents and Multiagents Systems},
  publisher = {International Foundation for Autonomous Agents and Multiagent Systems},
  year = {2016},
  pages = {1469-1470}
}
2016 Hosseini, S.A., Modgil, S. and Rodrigues, O., Assigning Likelihoods to Interlocutors' Beliefs and Arguments, Vol. 287, Frontiers in Artificial Intelligence and Applications, pp. 339-350, DOI: 10.3233/978-1-61499-686-6-339, 2016.

[BibTeX]

 URL PDF
BibTeX: 
@inproceedings{hosseini-modgil-rodrigues:16d,
  author = {S. A Hosseini and S. Modgil and O. Rodrigues},
  title = {Assigning Likelihoods to Interlocutors' Beliefs and Arguments},
  booktitle = {Frontiers in Artificial Intelligence and Applications},
  year = {2016},
  volume = {287},
  pages = {339-350},
  doi = {https://doi.org/10.3233/978-1-61499-686-6-339}
}
2016 Rodrigues, O., Introducing EqArgSolver: An argumentation solver using equational semantics, 2016.

[BibTeX]

  PDF
BibTeX: 
@misc{rodrigues:16e,
  author = {O. Rodrigues},
  title = {Introducing EqArgSolver: An argumentation solver using equational semantics},
  year = {2016},
  note = {The First International Workshop on Systems and Algorithms for Formal Argumentation, colocated with COMMA 2016}
}
2016 Young, A., Modgil, S. and Rodrigues, O., Prioritised Default Logic as Rational Argumentation, Proceedings of the 2016 International Conference on Autonomous Agents and Multiagents Systems, pp. 626-634, 2016.

[BibTeX]

  PDF
BibTeX: 
@inproceedings{young-modgil-rodrigues:16,
  author = {A. Young and S. Modgil and O. Rodrigues},
  title = {Prioritised Default Logic as Rational Argumentation},
  booktitle = {Proceedings of the 2016 International Conference on Autonomous Agents and Multiagents Systems},
  publisher = {International Foundation for Autonomous Agents and Multiagent Systems},
  year = {2016},
  pages = {626-634},
  url = {http://dl.acm.org/citation.cfm?id=2936924.2937018}
}
2015 Gabbay, D.M. and Rodrigues, O., Equilibrium States in Numerical Argumentation Networks, Logica Universalis, pp. 1-63, DOI: 10.1007/s11787-015-0119-7, 2015.

[BibTeX]

 URL PDF
BibTeX: 
@article{esnan-15,
  author = {Gabbay, D. M. and Rodrigues, O.},
  title = {Equilibrium States in Numerical Argumentation Networks},
  journal = {Logica Universalis},
  publisher = {Springer Basel},
  year = {2015},
  pages = {1-63},
  url = {http://dx.doi.org/10.1007/s11787-015-0119-7},
  doi = {https://doi.org/10.1007/s11787-015-0119-7}
}
2015 Meneguzzi, F., Rodrigues, O., Oren, N., Vasconcelos, W.W. and Luck, M., BDI reasoning with normative considerations, Engineering Applications of Artificial Intelligence, Vol. 43 (0), pp. 127 - 146, DOI: http://dx.doi.org/10.1016/j.engappai.2015.04.011, 2015.

[BibTeX]

 URL PDF
BibTeX: 
@article{Meneguzzi2015127,
  author = {F. Meneguzzi and O. Rodrigues and N. Oren and W. W. Vasconcelos and M. Luck},
  title = {BDI reasoning with normative considerations},
  journal = {Engineering Applications of Artificial Intelligence},
  year = {2015},
  volume = {43},
  number = {0},
  pages = {127 - 146},
  url = {http://www.sciencedirect.com/science/article/pii/S0952197615000925},
  doi = {https://doi.org/10.1016/j.engappai.2015.04.011}
}
2015 Gabbay, D.M. and Rodrigues, O., Probabilistic Argumentation: An Equational Approach., Logica Universalis, Vol. 9 (3), pp. 345-382, 2015.

[BibTeX]

  PDF
BibTeX: 
@article{prob-argum:15,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {Probabilistic Argumentation: An Equational Approach.},
  journal = {Logica Universalis},
  year = {2015},
  volume = {9},
  number = {3},
  pages = {345-382}
}
2014 Gabbay, D.M. and Rodrigues, O., A self-correcting iteration schema for argumentation networks, Proceedings of COMMA V, pp. 377 - 384, DOI: 10.3233/978-1-61499-436-7-377, 2014.

[BibTeX]

 URL PDF
BibTeX: 
@inproceedings{gabbay-rodrigues:COMMA2014,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {A self-correcting iteration schema for argumentation networks},
  booktitle = {Proceedings of COMMA V},
  publisher = {IOS Press},
  year = {2014},
  pages = {377 - 384},
  doi = {https://doi.org/10.3233/978-1-61499-436-7-377}
}
2014 Gabbay, D.M. and Rodrigues, O., An Equational Approach to the Merging of Argumentation Networks, Journal of Logic and Computation, Vol. 24, pp. 1253-1277, 2014.

[BibTeX]
BibTeX: 
@article{gabbay-rodrigues-jlc:13,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {An Equational Approach to the Merging of Argumentation Networks},
  journal = {Journal of Logic and Computation},
  publisher = {OUP},
  year = {2014},
  volume = {24},
  pages = {1253-1277}
}
2014 Hosseini, S.A., Modgil, S. and Rodrigues, O., Enthymeme Construction in Dialogues using Shared Knowledge, Proceedings of COMMA V, pp. 325-332, DOI: 10.3233/978-1-61499-436-7-325, 2014.

[BibTeX]

 URL PDF
BibTeX: 
@inproceedings{hosseini-modgil-rodrigues:COMMA2014,
  author = {S. A. Hosseini and S. Modgil and O. Rodrigues},
  title = {Enthymeme Construction in Dialogues using Shared Knowledge},
  booktitle = {Proceedings of COMMA V},
  publisher = {IOS Press},
  year = {2014},
  pages = {325-332},
  doi = {https://doi.org/10.3233/978-1-61499-436-7-325}
}
2012 Gabbay, D.M. and Rodrigues, O., A Numerical Approach to the Merging of Argumentation Networks, Proceedings of CLIMA XIII, pp. 195-212, 2012.

[BibTeX]
BibTeX: 
@inproceedings{gabbay-rodrigues:12,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {A Numerical Approach to the Merging of Argumentation Networks},
  booktitle = {Proceedings of CLIMA XIII},
  publisher = {Springer-Verlag},
  year = {2012},
  pages = {195-212}
}
2011 Rodrigues, O., Gabbay, D. and Russo, A., Belief Revision, Handbook of Philosophical Logic: Volume 16, pp. 1-114, DOI: 10.1007/978-94-007-0479-4_1, 2011.

[BibTeX]

 URL
BibTeX: 
@incollection{Rodrigues:2011,
  author = {Odinaldo Rodrigues and Dov Gabbay and Alessandra Russo},
  title = {Belief Revision},
  booktitle = {Handbook of Philosophical Logic: Volume 16},
  publisher = {Springer Netherlands},
  year = {2011},
  pages = {1--114},
  url = {https://doi.org/10.1007/978-94-007-0479-4_1},
  doi = {https://doi.org/10.1007/978-94-007-0479-4_1}
}
2010 Gabbay, D., Rodrigues, O. and Russo, A., Revision, Acceptability and Context: Theoretic and Algorithmic Aspects, pp. 386, DOI: 10.1007/978-3-642-14159-1, 2010.

[BibTeX]

 URL
BibTeX: 
@book{rac:2010,
  author = {Gabbay, D and Rodrigues, O and Russo, A},
  title = {Revision, Acceptability and Context: Theoretic and Algorithmic Aspects},
  publisher = {Springer Verlag},
  year = {2010},
  pages = {386},
  url = {http://dx.doi.org/10.1007/978-3-642-14159-1},
  doi = {https://doi.org/10.1007/978-3-642-14159-1}
}
2008 Rodrigues, O., Gabbay, D.M. and Russo, A., Belief Revision in Non-Classical Logics, Review of Symbolic Logic, Vol. 1, pp. 267-304, 2008.

[BibTeX]
BibTeX: 
@article{non-classical-2,
  author = {O. Rodrigues and D. M. Gabbay and A. Russo},
  title = {Belief Revision in Non-Classical Logics},
  journal = {Review of Symbolic Logic},
  year = {2008},
  volume = {1},
  pages = {267-304}
}
2006 Elsenbroich, C., Gabbay, D.M. and Rodrigues, O., Getting possibilities from the impossible, Proceedings of NMR-06, pp. 505-513, 2006.

[BibTeX]
BibTeX: 
@inproceedings{elsenbroich-gabbay-rodrigues06,
  author = {C. Elsenbroich and D. M. Gabbay and O. Rodrigues},
  title = {Getting possibilities from the impossible},
  booktitle = {Proceedings of NMR-06},
  publisher = {Institut fur Informatik},
  year = {2006},
  pages = {505-513},
  note = {ISSN 1860-8477}
}
2006 Gabbay, D.M., Pigozzi, G. and Rodrigues, O., Belief revision, belief merging and voting, Proceedings of the Seventh Conference on Logic and the Foundations of Games and Decision Theory (LOFT06), pp. 71-78, 2006.

[BibTeX]
BibTeX: 
@inproceedings{pigozzi-gabbay-rodrigues06,
  author = {D. M. Gabbay and G. Pigozzi and O. Rodrigues},
  title = {Belief revision, belief merging and voting},
  booktitle = {Proceedings of the Seventh Conference on Logic and the Foundations of Games and Decision Theory (LOFT06)},
  publisher = {University of Liverpool},
  year = {2006},
  pages = {71-78}
}
2005 Rodrigues, O., Iterated Revision and Automatic Similarity Generation, Vol. 2, We will show them! Essays in honour of D. M. Gabbay, pp. 591-613, 2005.

[BibTeX]
BibTeX: 
@inbook{rodrigues05,
  author = {O. Rodrigues},
  title = {Iterated Revision and Automatic Similarity Generation},
  booktitle = {We will show them! Essays in honour of D. M. Gabbay},
  publisher = {College Publications},
  year = {2005},
  volume = {2},
  pages = {591-613}
}
2004 Gabbay, D.M., Rodrigues, O. and Woods, J., Deletion in Resource Unbounded Logics - Belief Contraction, Anti-Formulae and Resource Overdraft: Part II, Vol. 1, Logic, Epistemology and the Unity of Science, pp. 291-326, 2004.

[BibTeX]
BibTeX: 
@incollection{gabbay-rodrigues-woods04,
  author = {D. M. Gabbay and O. Rodrigues and J. Woods},
  title = {Deletion in Resource Unbounded Logics - Belief Contraction, Anti-Formulae and Resource Overdraft: Part II},
  booktitle = {Logic, Epistemology and the Unity of Science},
  publisher = {Kluwer Academic Publishers},
  year = {2004},
  volume = {1},
  pages = {291-326}
}
2004 Rodrigues, O., d'Avila Garcez, A. and Russo, A., Reasoning about Requirements Evolution Using Clustered Belief Revision, Advances in Artificial Intelligence, Proceedings of 17th SBIA, pp. 41-51, 2004.

[BibTeX]
BibTeX: 
@inproceedings{se:sbia,
  author = {O. Rodrigues and A. d'Avila Garcez and A. Russo},
  title = {Reasoning about Requirements Evolution Using Clustered Belief Revision},
  booktitle = {Advances in Artificial Intelligence, Proceedings of 17th SBIA},
  publisher = {Springer-Verlag Berlin Heidelberg},
  year = {2004},
  pages = {41-51},
  note = {LNAI 3171}
}
2003 Rodrigues, O., Structured Clusters: A Framework to Reason with Contradictory Interests, Journal of Logic and Computation, Vol. 13 (1), pp. 69-97, 2003.

[BibTeX]
BibTeX: 
@article{clusters,
  author = {O. Rodrigues},
  title = {Structured Clusters: A Framework to Reason with Contradictory Interests},
  journal = {Journal of Logic and Computation},
  year = {2003},
  volume = {13},
  number = {1},
  pages = {69-97}
}
2003 Rodrigues, O., d'Avila Garcez, A. and Russo, A., Reasoning about Requirements Evolution Using Clustered Belief Revision, Proceedings of ACM ESEC/FSE International Workshop on Intelligent Technologies for Software Engineering WITSE03, 2003.

[BibTeX]
BibTeX: 
@inproceedings{rodrigues-garcez-russo03,
  author = {O. Rodrigues and A. d'Avila Garcez and A. Russo},
  title = {Reasoning about Requirements Evolution Using Clustered Belief Revision},
  booktitle = {Proceedings of ACM ESEC/FSE International Workshop on Intelligent Technologies for Software Engineering WITSE03},
  year = {2003}
}
2002 Gabbay, D.M., Rodrigues, O. and Woods, J., Belief Contraction, Anti-Formulae and Resource Overdraft: Part I - Deletion in Resource Bounded Logics, Logic Journal of the IGPL, Vol. 10 (6), pp. 601-652, 2002.

[BibTeX]
BibTeX: 
@article{gabbay-rodrigues-woods02,
  author = {D. M. Gabbay and O. Rodrigues and J. Woods},
  title = {Belief Contraction, Anti-Formulae and Resource Overdraft: Part I - Deletion in Resource Bounded Logics},
  journal = {Logic Journal of the IGPL},
  year = {2002},
  volume = {10},
  number = {6},
  pages = {601-652}
}
1999 Gabbay, D.M., Rodrigues, O. and Russo, A., Information, Uncertainty, Fusion, pp. 3-31, 1999.

[BibTeX]
BibTeX: 
@inbook{gabbay-rodrigues-russo99,
  author = {D. M. Gabbay and O. Rodrigues and A. Russo},
  title = {Information, Uncertainty, Fusion},
  publisher = {Kluwer Academic Publishers},
  year = {1999},
  pages = {3-31},
  note = {ISBN: 0-7923-8590-X}
}
1998 Rodrigues, O., A methodology for iterated information changeSchool: Department of Computing, Imperial College, 1998.

[BibTeX]

  PDF
BibTeX: 
@phdthesis{rodrigues98,
  author = {O. Rodrigues},
  title = {A methodology for iterated information change},
  school = {Department of Computing, Imperial College},
  year = {1998}
}
1997 Gabbay, D.M. and Rodrigues, O., Structured Belief Bases: a practical approach to prioritised base revision, Proceedings of First Internation Joint Conference on Qualitative and Quantitative Practical Reasoning, pp. 267-281, 1997.

[BibTeX]
BibTeX: 
@inproceedings{gabbay-rodr:97-a,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {Structured Belief Bases: a practical approach to prioritised base revision},
  booktitle = {Proceedings of First Internation Joint Conference on Qualitative and Quantitative Practical Reasoning},
  publisher = {Springer-Verlag},
  year = {1997},
  pages = {267-281}
}
1996 Gabbay, D.M. and Rodrigues, O., A methodology for iterated Theory Change, Practical Reasoning - First International Conference on Formal and Applied Practical Reasoning, FAPR'96, 1996.

[BibTeX]
BibTeX: 
@inproceedings{gabbay-rodr:96-a,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {A methodology for iterated Theory Change},
  booktitle = {Practical Reasoning - First International Conference on Formal and Applied Practical Reasoning, FAPR'96},
  publisher = {Springer Verlag},
  year = {1996}
}
1996 Gabbay, D.M. and Rodrigues, O., Structured Databases: a framework to reason about Belief Change, Proceedings of the Theory and Formal Methods 1996 workshop, 1996.

[BibTeX]
BibTeX: 
@inproceedings{gabbay-rodrigues96-b,
  author = {D. M. Gabbay and O. Rodrigues},
  title = {Structured Databases: a framework to reason about Belief Change},
  booktitle = {Proceedings of the Theory and Formal Methods 1996 workshop},
  publisher = {Imperial College Press},
  year = {1996}
}
1996 Rodrigues, O., Ryan, M. and Schobbens, P.-Y., Counterfactuals and updates as inverse modalities, 6th Conference on Theoretical Aspects of Rationality and Knowledge, pp. 163-174, 1996.

[BibTeX]
BibTeX: 
@inproceedings{rodr-ryan-schob:96,
  author = {O. Rodrigues and M. Ryan and P.-Y. Schobbens},
  title = {Counterfactuals and updates as inverse modalities},
  booktitle = {6th Conference on Theoretical Aspects of Rationality and Knowledge},
  year = {1996},
  pages = {163-174}
}
1994 Rodrigues, O. and Benevides, M., PROMAL — Programming in modal action logic, Vol. 844, Programming Language Implementation and Logic Programming, pp. 457-458, DOI: 10.1007/3-540-58402-1_36, 1994.

[BibTeX]

 URL
BibTeX: 
@incollection{promal:94,
  author = {Rodrigues, Odinaldo and Benevides, Mario},
  title = {PROMAL — Programming in modal action logic},
  booktitle = {Programming Language Implementation and Logic Programming},
  publisher = {Springer Berlin Heidelberg},
  year = {1994},
  volume = {844},
  pages = {457-458},
  url = {http://dx.doi.org/10.1007/3-540-58402-1_36},
  doi = {https://doi.org/10.1007/3-540-58402-1_36}
}
1994 Rodrigues, O. and Benevides, M.R.F., Belief Revision in Pseudo-Definite Sets, Proceedings of the 11th Brazilian Symposium on Artificial Intelligence (SBIA '94), 1994.

[BibTeX]
BibTeX: 
@inproceedings{rodrigues-benevides94,
  author = {O. Rodrigues and M. R. F. Benevides},
  title = {Belief Revision in Pseudo-Definite Sets},
  booktitle = {Proceedings of the 11th Brazilian Symposium on Artificial Intelligence (SBIA '94)},
  year = {1994}
}
1993 Rodrigues, O., Prolog Modal de Ação e Revisão de Crenças em Conjuntos DefinidosSchool: COPPE - Universidade Federal do Rio de Janeiro - Brazil, 1993.

[BibTeX]
BibTeX: 
@mastersthesis{rodrigues93,
  author = {O. Rodrigues},
  title = {Prolog Modal de Ação e Revisão de Crenças em Conjuntos Definidos},
  school = {COPPE - Universidade Federal do Rio de Janeiro - Brazil},
  year = {1993},
  note = {Published in the Federal University of Rio de Janeiro, Brazil}
}
1993 Rodrigues, O. and Benevides, M.R.F., Revisão de Cren¸ cas em Conjuntos de CláusulasSchool: COPPE/UFRJ, Rio de Janeiro-RJ, BRAZIL, 1993.

[BibTeX]
BibTeX: 
@techreport{rodrigues-benevides93,
  author = {O. Rodrigues and M. R. F. Benevides},
  title = {Revisão de Cren¸ cas em Conjuntos de Cláusulas},
  school = {COPPE/UFRJ, Rio de Janeiro-RJ, BRAZIL},
  year = {1993},
  note = {Publica¸ cões Técnicas, ES-281/93}
}
1992 Rodrigues, O. and Benevides, M.R.F., Prolog Modal de Ação, Anais do IX SBIA, pp. 339-357, 1992.

[BibTeX]
BibTeX: 
@inproceedings{rodrigues-benevides92,
  author = {O. Rodrigues and M. R. F. Benevides},
  title = {Prolog Modal de Ação},
  booktitle = {Anais do IX SBIA},
  year = {1992},
  pages = {339-357}
}

Books

Revision, Acceptability and Context: Theoretic and Algorithmic Aspects

   Springer, 2010.

Elementary Logic with Applications: A Procedural Perspective for Computer Scientists

   College Publications, 2016.

Short Biography

Although my research is mostly theoretical I have always had a keen interest in the most practical implementation aspects. Computing, and consequently technology, is both my passion and my natural element. This has been the case throughout my life.

I started programming when I was very young (at around 15yo) in the days when a personal computer consisted of a TV attached to an 8-bit "computer" and programs were saved to cassete tapes. You could actually hear the phone ring and the modem tick when you wanted to connect to a remote server. In those days very little support was available to a programmer. BASIC was the most common language keen teenagers like me would use with their computers, but some things we had to do in assembler, a very rudimentary form of machine language. Then PCs came along, programming languages improved (we had Turbo Pascal, then Delphi), and commercial opportunities to make a living out of programming started to become more widespread beyond the realm of mainframes and dumb terminals. That's when a few of us at the University of Fortaleza, myself included, started opening companies and writing software professionally. I remember the first POS system I wrote, where I even had to implement a rudimentary locking mechanism myself to avoid the lost update problem, common in database systems. No database servers were available at the consumer level and only big organisations could afford them, but smaller businesses were seeing the potential for automating some core activities, such as sales, stock control, and reporting, and a few others needed the flexibility and speed that a computer could offer, for instance when calculating the forces applied to a structure supporting a roof. These were the types of problems that spurred my curiosity as a teenager. But if we could solve those problems with a computer, could a machine actually think, or at least behave as if it could?

I quickly realised that I needed to study more, so I applied for a MSc in Artificial Intelligence at COPPE, in the Federal University of Rio de Janeiro, some 3000km away from the city I lived in. The masters then led me to a PhD in Artificial Intelligence, this time even farther away at Imperial College London, 9000km away from Rio.

My first job after my PhD was as Research Assistant in a project involving the development of data-driven algorithms for artificial intelligence. In retrospect, that project was very ahead of its time in 1998.

I am currently Senior Lecturer at King's College London and have taught thousands of students in most of the core computing disciplines: database systems, distributed systems, C++ programming, computational logic, internet systems, artificial language, classical logic, and the like.

I have had a wide variety of administrative duties including publications and publicity, MSc admissions, and more recently I have been chairing the Computing Committee, initially for the Department of Informatics and in the last few years for the whole Faculty of Natural and Mathematical Sciences. Throughout this period, we have seen good progress and exciting new things hapenning at King's, including the inception of HPC facilities such as ADA and Rosalind.

In recent years, my research has veered towards the more practical aspects of common-sense reasoning, particularly in the area of argumentation theory. From dialogues to semantics, including devising numerical methods for argumentation systems and investigating all aspects related to their implementation.

Last year I submitted the prototype of a numerical solver to the first International Competition on Computational Models of Argumentation called GRIS based on theoretical research I had done on numerical argumentation. The prototype showed potential and I have since been working towards implementing a more robust solver called EqArgSolver. The significance of an argumentation solver such as EqArgSolver is that, unlike in reduction-based solvers, it operates on the argumentation graph directly. This puts it in a more robust position to tackle future argumentation problems that may not be possible to solve using reduction-based solvers.

EqArgSolver is not yet ready for general release, but following recent theoretical work, I have implemented a faster core component to replace GRIS' and the development version has already shown up to 12x increase in performance in comparison to GRIS. I have presented these developments in the recent SAFA workshop co-located with COMMA 16. Before EqArgSolver is ready for the next ICCMA, a new key algorithm needs to be developed and shown to be correct before its subsequent implementation. This is currently under way.

Argumentation Solvers

Computation of Argumentation Semantics

EqArgSolver is an argumentation solver that can be used to compute solutions to enumeration and decision problems in the grounded, complete, preferred and stable semantics.

EqArgSolver supersedes GRIS, which was submitted to the 1st International Competition on Computational Models of Argumentation.

EqArgSolver provide a more comprehensive range of semantics, has a smaller memory footprint, and it is up to 12x faster than GRIS. EqArgSolver will be available for general release in Spring 2017. Please check this page for further announcements.

More details about EqArgSolver can be found here.

Research projects

  • EPSRC grant number EP/E034446/1, Connections between belief revision, belief merging and voting, 2006
  • EPSRC grant number GR/R44706/01, Belief Contraction and Anti-Formulae. Logical Modelling of Deletion, 2002-2005

BSc/MSci Projects 2019/2020

Besides being part of an important and well-studied problem in AI, the projects below aim to improve your overall design, reasoning and programming skills.

These projects will maximise your professional development and take your programming abilities to the next level.

  1. Artificial Intelligence: A solver for argumentation frameworks [Multiple options]

    In Artificial Intelligence, a practical reasoning problem is how to make sense of a multitude of point-of-views or arguments that interact by attacking and supporting each other. This type of scenario is important in public debates and the automation of common-sense reasoning tasks in general. The arguments and how they relate to each other can be modelled by a so-called Abstract Argumentation Framework.

    An Abstract Argumentation Framework is a tuple , where A is a set of arguments and R is an attack relation on A x A. Argumentation theory provides a means of deciding which arguments "win" based on the attack relationship of these arguments. An extension is the set of winning arguments under a particular semantics.

    Deciding whether a subset of A is an extension of an argumentation framework is a complex problem, and cannot be done by hand for all but the simplest example. Instead, computer programs called argumentation solvers are built for this and for a number of other important reasoning problems.

    The objective of this project is to explore this problem as much as possible and come up with an efficient implementation to check whether a given set is an extension of an argumentation framework and/or calculate all extensions of such a framework. In order words, you will have to build an actual solver similar to the ones that compete in the bi-annual International Competition on Computational Models of Argumentation (ICCMA): http://argumentationcompetition.org/

    We are not concerned with the visualisation of the graphs which can be performed by a different application.

    This project consists of an implementation and an evaluation against the solver EqArgSolver, used in the competition. You are free to choose the approach of the implementation (direct/translation), the implementation language, and the algorithm, but your solver will be evaluated against state-of-the-art implementations.

    This is a great opportunity for you to extend your programming ability, write a sophisticated piece of software to specification and evaluate its efficiency against international benchmarks. It will require solutions for several complex problems in computer science: efficient data representation, management of complex control structures, memory management, etc.

    Skills required

    • Basic computer science concepts: graphs, graph traversal, algorithms
    • interface and integration of system components
    • one of JAVA, C++, Python, etc
    • understanding of logic encodings (for SAT-based solvers)

    Skills required

    • Basic computer science concepts: graphs, graph traversal, algorithms
    • interface and integration of system components
    • one of JAVA, C++, Python, etc
    • understanding of logic encodings (for SAT-based solvers)

  2. Artificial Intelligence: A graph visualisation and manipulation tool for argumentation frameworks

    There are some graph visualisation programs freely available: yEd, gephi and Tulip, are only a few of them.

    Some of these graph visualisation tools can be extended but only offer functionality for general graphs. In Artificial Intelligence, a special type of graphs called argumentation frameworks are increasingly used in reasoning problems. To this date, it is difficult to create, visualise and interact with these graphs in a seamless and efficient manner.

    The objective of this project is to develop a sophisticated application for graph visualisation to aid with the problems described above. The project allows for a variation of approaches to be decided upon commencement of the project. You can either design a complete new application from the ground up, or extend the functionality of an already existing application of your choice to enable them to deal with argumentation frameworks.

    Skills required

    • basic computer science concepts: graphs, graph traversal, algorithms
    • interface and integration of system components
    • JAVA or C++

  3. Artificial Intelligence: Design and Implementation of metrics for directed graphs

    A directed graph is a data structure of the <A,R>, where A is a set of nodes and R is a set of ordered pairs (x,y) indicating a relationship from x to y. Graphs are used in a multitude of situations. Two recent and important applications include the relationships between users of a social network and an abstract argumentation framework, which depicts the attack relations between arguments.

    Graphs can be analysed and compared using metrics that measure a particular property of interest to an application. For example, in social networks, an important problem is the identification of influential nodes, because they make the dissemination of information easier. Similarly, some abstract argumentation frameworks have structural properties that makes computing solutions to some problems easier. The objective of this project is to propose and implement metrics for argumentation frameworks and social networks. Some of existing metrics include density, sparsity, etc. It is hoped that these metrics will help to understand the complexity of solving specific problems in these application areas.

    This project involves a mixture of advanced research content with direct practical implementation in areas of increasing interest in Artificial Intelligence.

    Skills required

    • basic computer science concepts: graphs, graph traversal, algorithms
    • basic argumentation theory, concepts on social networks (can be easily acquired)
    • interface and integration of system components
    • JAVA or C++

MSc project for 2019-2020

  1. [OR-M1] Collaborative environment mapping probes [Multiple Options]

    Imagine a virtual environment with a pre-defined boundary and some internal objects that need to be mapped by some virtual agents as efficiently as possible.

    Your objective is to produce a global map of this environment based on information collected by the probes which are initially placed randomly in the environment and have the ability to move about and detect objects and the boundary in front of them.

    You need to assume that the probes have limited ability to move (they may run out of power, for instance), so you need to map the environment as efficiently as possible. In order to compare different mapping strategies, you need to devise your own metrics to evaluate how good each mapping is.

    Part of your project is to research and choose an appropriate simulation environment such as GridWorld providing basic functionality and some visualisation of the exploration.

    The core of your project will be on the design of efficient mapping strategies but you must suggest, design and implement some basic communication and coordination aspects between the probes. For example, you may want to share the areas of the environment currently mapped, so as to avoid one of the probes going over an area that has already been mapped. You will also need to produce a single map of the environment combining the individual bits mapped by each probe separately.


    Possible Applications
    • Autonomous vehicles attending disaster zones
    • Space probes mapping external planets
    • Vacuum cleaners and autonomous vehicles
    Deliverables
    • A visualisation of the environment as it is being explored by the probes
    • A mapping strategy detailing how each probe explores the environment
    • Metrics to evaluate the efficiency of the mapping
    • Communication and coordination protocols between the probes, with adaptive strategies to make the mapping as efficient as possible

Office hours

  • Mondays, 12:30pm-2:30pm
Students do not need an appointment to see me during office hours.

Trivia

Things I like to do

  • Write a bit of code: JAVA, C++, PHP, HTML, etc.
  • Play with my camera
  • Read books and stuff
  • Drink a lot of coffee
  • Fix the world
  • Learn about technology
  • Ride my bike
  • Travel the world
  • Maths and computing

Contact details

Dr. Odinaldo Rodrigues
King's College London
Department of Informatics
London, WC2B 4BG, UK
e-mail: odinaldo.rodrigues@kcl.ac.uk
Tel.: +44 20 7848 2087
Fax: +44 20 7848 2851
Bush House, Strand Campus
Office: BH(N)7.08