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The Complexity of Conjunctive Query Abduction in DL-Lite

Diego Calvanese, Magdalena Ortiz, Mantas Simkus, Giorgio Stefanoni
2011 International Workshop on Description Logics  
We address this latter problem for (conjunctive) query answering over DL-Lite ontologies, by adopting abductive reasoning, that is, we look for additions to the ABox that force a given tuple to be in the  ...  This holds also for DLs, where research focused on the explanation of both TBox reasoning and, more recently, query answering.  ...  In fact, conjunctive query answering in DL-Lite A enjoys FOL-rewritability, i.e., it can be reduced to the problem of evaluating a suitably constructed FOL query over a database instance.  ... 
dblp:conf/dlog/CalvaneseOSS11 fatcat:zko2j7hnn5hcleicl3hsutb374

Reasoning about Explanations for Negative Query Answers in DL-Lite

D. Calvanese, M. Ortiz, M. Simkus, G. Stefanoni
2013 The Journal of Artificial Intelligence Research  
We address the latter problem for instance and conjunctive query answering over DL-Lite ontologies by adopting abductive reasoning; that is, we look for additions to the ABox that force a given tuple to  ...  Besides explaining the presence of a tuple in a query answer, it is important to explain also why a given tuple is missing.  ...  Acknowledgments The authors would like to thank the anonymous referees for their careful reading of the submitted manuscript and their valuable comments.  ... 
doi:10.1613/jair.3870 fatcat:jq2kjkbytvesplbuw6yhl4ol4e

A Tractable Approach to ABox Abduction over Description Logic Ontologies

Jianfeng Du, Kewen Wang, Yi-Dong Shen
2014 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
We focus on practical computation for a general problem of ABox abduction, called the query abduction problem, where an observation is a Boolean conjunctive query and the explanations may contain fresh  ...  We develop a tractable method (in data complexity) for computing all representative explanations in a consistent ontology. xperimental results demonstrate that the method is efficient and scalable for  ...  Acknowledgements This work is partly supported by NSFC grants (61375056, 61005043 and 61379043), Business Intelligence Key Team of Guangdong University of Foreign Studies (TD1202), Guangdong Natural Science  ... 
doi:10.1609/aaai.v28i1.8852 fatcat:jyyb3v5ldjbelf52g34yi2dkie

Query-driven Repairing of Inconsistent DL-Lite Knowledge Bases (Extended Abstract)

Meghyn Bienvenu, Camille Bourgaux, François Goasdoué
2016 International Workshop on Description Logics  
The difficulty of computing the necessarily (non)false assertions correlates with the number of relevant assertions induced by QRPs and the observed times seem reasonable in practice.  ...  In our experiments, deciding if a potential solution exists, and computing the relevant assertions, takes a few milliseconds.  ...  Both semantics have appealing computational properties: for most DL-Lite dialects, including DL-Lite R , conjunctive query answering is tractable in data complexity [18, 7] .  ... 
dblp:conf/dlog/BienvenuBG16 fatcat:zhgb3msc5jcsdfcb67oicoompm

Prediction and Explanation over DL-Lite Data Streams [chapter]

Szymon Klarman, Thomas Meyer
2013 Lecture Notes in Computer Science  
In this paper, we consider data represented in Description Logics from the popular DL-Lite family, and study the logic foundations of prediction and explanation over DL-Lite data streams, i.e., reasoning  ...  Further, we analyse the computational complexity of reasoning with rules expressed in different fragments of the temporal language.  ...  In the next section, we recap preliminaries of DLs and conjunctive query answering.  ... 
doi:10.1007/978-3-642-45221-5_36 fatcat:brqntcvb2zh3jgemvxc6fqrt4u

An Abductive Framework for Datalog± Ontologies

Marco Gavanelli, Evelina Lamma, Fabrizio Riguzzi, Elena Bellodi, Riccardo Zese, Giuseppe Cota
2015 International Conference on Logic Programming  
Datalog ± is an extension of Datalog which can be used for representing lightweight ontologies, and is able to express the DL-Lite family of ontology languages, with tractable query answering under certain  ...  Description Logics (DLs) are often the languages of choice for modeling ontologies. Great effort has been spent in identifying decidable or even tractable fragments of DLs.  ...  Extensive work has focused on developing tractable DLs, identifying the DL-Lite family (Calvanese et al. 2007) , for which answering conjunctive queries is in AC 0 in data complexity.  ... 
dblp:conf/iclp/GavanelliLRBZC15 fatcat:hl34cs4iljhqxebhaz4u3oqaki

Abductive logic programming for Datalog +/- ontologies

Marco Gavanelli, Evelina Lamma, Fabrizio Riguzzi, Elena Bellodi, Riccardo Zese, Giuseppe Cota
2015 Italian Conference on Computational Logic  
Datalog ± is an extension of Datalog which can be used for representing lightweight ontologies, and is able to express the DL-Lite family of ontology languages, with tractable query answering under certain  ...  Description Logics (DLs) are often the languages of choice for modeling ontologies. Great effort has been spent in identifying decidable or even tractable fragments of DLs.  ...  Extensive work focused on developing tractable DLs, identifying the DL-Lite family [14] , for which answering conjunctive queries is in AC 0 in data complexity.  ... 
dblp:conf/cilc/GavanelliLRBZC15 fatcat:hs77pjjedbfb3hoirnnf2he7li

Querying Inconsistent Description Logic Knowledge Bases under Preferred Repair Semantics

Meghyn Bienvenu, Camille Bourgaux, François Goasdoué
2014 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
We analyze the complexity of query answering under the resulting semantics, focusing on the lightweight logic DL-Lite_R.  ...  Unsurprisingly, query answering is intractable in all cases, but we nonetheless identify one notion of preferred repair, based upon priority levels, whose data complexity is "only" coNP-complete.  ...  Acknowledgements The authors acknowledge Despoina Trivela for her work on an early version of the system. This work was supported by the ANR project PAGODA (ANR-12-JS02-007-01).  ... 
doi:10.1609/aaai.v28i1.8855 fatcat:mrur5roeo5cy3g5t6hxs2vpbwi

Incosistency-Tolerant Forgetting in DL-lite

Peng Xiao, Kewen Wang, Zhe Wang
2017 International Semantic Web Conference  
Acknowledgement This work was partially supported by the Australian Research Council (ARC) under grant DP130102302.  ...  In DL-Lite core , the computation of γ-forgetting is in P for γ being IAR or ICAR with respect to data complexity.  ...  The concepts and roles of DL-lite core are defined by B → A | ∃R, R → P | P − , C → B | ¬B where A is a concept name and R is a role name. An inclusion axiom in DL-lite core is of the form B C.  ... 
dblp:conf/semweb/XiaoWW17 fatcat:4iqwvo4jkze6xcbwvgfptyl2am

Ontologies and Data Management: A Brief Survey

Thomas Schneider, Mantas Šimkus
2020 Künstliche Intelligenz  
In order to align and complete data, systems may rely on taxonomies and background knowledge that are provided in the form of an ontology.  ...  This survey gives an overview of research work on the use of ontologies for accessing incomplete and/or heterogeneous data.  ...  as you give appropriate credit to the original author(s) and the source,  ... 
doi:10.1007/s13218-020-00686-3 pmid:32999532 pmcid:PMC7497697 fatcat:zeskjfjrpvcojjh6q3yjzhlyci

Towards Tractable and Practical ABox Abduction over Inconsistent Description Logic Ontologies

Jianfeng Du, Kewen Wang, Yi-Dong Shen
2015 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
, and propose the notion of IAR-explanations in inconsistent DL ontologies.  ...  ABox abduction plays an important role in reasoning over description logic (DL) ontologies. However, it does not work with inconsistent DL ontologies.  ...  Acknowledgements This work is partly supported by NSFC grants (61375056, 61005043 and 61379043), Business Intelligence Key Team of Guangdong University of Foreign Studies (TD1202), Guangdong Natural Science  ... 
doi:10.1609/aaai.v29i1.9393 fatcat:c3hvpknhnffi7hxelf3gktd5ju

Getting unique solution in data exchange

Nhung Ngo, Enrico Franconi
2013 Proceedings of the VLDB Endowment  
This fact causes many problems in query answering over target data for non-conjunctive queries.  ...  To make query answering feasible for all queries, we focus on a methodology for extending the original schema mapping to guarantee the uniqueness of target instance corresponding to a source instance.  ...  At the first stage, we have focused on DL-Lite TBox. Regarding to the language of minimal solution, we proposed sts fragment. In general, the fragment is undecidable.  ... 
doi:10.14778/2536274.2536332 fatcat:faqknfzjkvhgjngdh7y6xy67zy

Finding Good Proofs for Answers to Conjunctive Queries Mediated by Lightweight Ontologies (Technical Report) [article]

Christian Alrabbaa and Stefan Borgwardt and Patrick Koopmann and Alisa Kovtunova
2022 arXiv   pre-print
By distinguishing various parameters such as the shape of a query, we obtain an overview of the complexity of this problem for the lightweight ontology languages DL-Lite_R and EL, and also have a brief  ...  We investigate the data and combined complexity of determining the existence of a proof below a given quality threshold, which can be measured in different ways.  ...  Acknowledgments This work was supported by DFG in grant 389792660, TRR 248 (https://perspicuous-computing.science), and QuantLA, GRK 1763 (https://lat.inf.tu-dresden.de/quantla).  ... 
arXiv:2206.09758v1 fatcat:v4jftlejwne7vilywn5ctfzdk4

Computing and Explaining Query Answers over Inconsistent DL-Lite Knowledge Bases

Meghyn Bienvenu, Camille Bourgaux, François Goasdoué
2019 The Journal of Artificial Intelligence Research  
We define explanations for positive and negative answers under the brave, AR and IAR semantics. We then study the computational properties of explanations in DL-LiteR.  ...  The first contribution of this paper is a practical approach for computing the query answers under three well-known such semantics, namely the AR, IAR and brave semantics, in the lightweight description  ...  Acknowledgments This work was supported by the ANR project PAGODA (ANR-12-JS02-007-01).  ... 
doi:10.1613/jair.1.11395 fatcat:5o7b52euq5duhei6m4mrp2lnba

Query Answering over Complete Data with Conceptual Constraints

Nhung Ngo
2016 Proceedings of the 2016 on SIGMOD'16 PhD Symposium - SIGMOD'16 PhD  
We first study the complexity of query answering problem under description logic constraints in the presence of complete data and show that complete data makes query answering become harder than query  ...  At the end, we study the definability abduction problem which aims to characterize the least committing extensions of conceptual constraints to gain the exact rewritable of queries.  ...  Acknowledgement This research is partially supported by Free University of Bolzano, under project ORMiE.  ... 
doi:10.1145/2926693.2929899 dblp:conf/sigmod/Ngo16 fatcat:o6f6vjbbnbeyrn5vzv4kdu54ny
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