Abstract
An Ontology-based Data Access system is constituted by an ontology, namely a description of the concepts and the relations in a domain of interest, a database storing facts about the domain, and a mapping between the data and the ontology. In this paper, we consider ontologies expressed in the popular DL-Lite family of Description Logic, and we address the problem of computing explanations for answers to queries in an OBDA system, where queries are either positive, in particular conjunctive queries, or negative, i.e., negation of conjunctive queries. We provide the following contributions: (i) we propose a formal, comprehensive framework of explaining query answers in OBDA systems based on DL-Lite; (ii) we present an algorithm that, given a tuple returned as an answer to a positive query, and given a weighting function, examines all the explanations of the answer, and chooses the best explanation according to such function; (iii) we do the same for the answers to negative queries. Notably, on the way to get the latter result, we present what appears to be the first algorithm that computes the answers to negative queries in DL-Lite.
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Notes
- 1.
For the sake of simplicity, we do not deal with attributes in this paper, but they can be added without any problem.
References
Baader, F., Calvanese, D., McGuinness, D.L., Nardi, D., Patel-Schneider, P.F. (eds.): The Description Logic Handbook: Theory, Implementation, and Applications. Cambridge University Press, New York (2003)
Borgida, A., Calvanese, D., Rodriguez-Muro, M.: Explanation in the DL-Lite family of description logics. In: Meersman, R., Tari, Z. (eds.) OTM 2008. LNCS, vol. 5332, pp. 1440–1457. Springer, Heidelberg (2008). https://doi.org/10.1007/978-3-540-88873-4_35
Calvanese, D., et al.: The mastro system for ontology-based data access. Semant. Web 2(1), 43–53 (2011)
Calvanese, D., De Giacomo, G., Lembo, D., Lenzerini, M., Rosati, R.: Tractable reasoning and efficient query answering in description logics: the DL-Lite family. J. Autom. Reasoning 39(3), 385–429 (2007)
Calvanese, D., Giacomo, G.D., Lembo, D., Lenzerini, M., Rosati, R.: Data complexity of query answering in description logics. Artif. Intell. 195, 335–360 (2013)
Calvanese, D., Ortiz, M., Simkus, M., Stefanoni, G.: Reasoning about explanations for negative query answers in DL-Lite. J. Artif. Intell. Res. 48, 635–669 (2013)
Eiter, T., Lutz, C., Ortiz, M., Simkus, M.: Answering in description logics with transitive roles. In: IJCAI (2009)
Horridge, M.: Justification based explanation in ontologies. Ph.D. thesis, University of Manchester, UK (2011)
Levesque, H.J., Brachman, R.J.: Expressiveness and tractability in knowledge representation and reasoning. Comput. Intell. 3, 78–93 (1987)
Lenzerini, M.: Ontology-based data management. In: Proceedings of the 20th ACM International Conference on Information and Knowledge Management, CIKM 2011, pp. 5–6. ACM, New York (2011)
Lenzerini, M.: Managing data through the lens of an ontology. AI Mag. 39(2), 65–74 (2018)
Penaloza, R., Sertkaya, B.: Understanding the complexity of axiom pinpointing in lightweight description logics. Artif. Intell. 250(Supplement C), 80–104 (2017)
Straccia, U.: Towards top-k query answering in description logics: the case of DL-Lite. In: Fisher, M., van der Hoek, W., Konev, B., Lisitsa, A. (eds.) JELIA 2006. LNCS (LNAI), vol. 4160, pp. 439–451. Springer, Heidelberg (2006). https://doi.org/10.1007/11853886_36
van Harmelen, F., Lifschitz, V., Porter, B.: Handbook of Knowledge Representation. Elsevier Science, San Diego (2007)
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Croce, F., Lenzerini, M. (2018). A Framework for Explaining Query Answers in DL-Lite. In: Faron Zucker, C., Ghidini, C., Napoli, A., Toussaint, Y. (eds) Knowledge Engineering and Knowledge Management. EKAW 2018. Lecture Notes in Computer Science(), vol 11313. Springer, Cham. https://doi.org/10.1007/978-3-030-03667-6_6
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