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Querying Factorized Probabilistic Triple Databases [chapter]

Denis Krompaß, Maximilian Nickel, Volker Tresp
2014 Lecture Notes in Computer Science  
In this paper we address the issue from the perspective of probabilistic databases, which account for uncertainty in the data via a probability distribution over all database instances.  ...  Data quality and completeness are key issues in many community-generated data stores, like LOD, which motivates probabilistic and statistical approaches to data representation, reasoning and querying.  ...  Section 5 contains the main contribution of the paper and addresses the querying of a factorized probabilistic triple databases.  ... 
doi:10.1007/978-3-319-11915-1_8 fatcat:j6cakwd6avgu7ln4nt7rmnnyea

DBrev: Dreaming of a Database Revolution

Gjergji Kasneci, Jurgen Van Gael, Thore Graepel
2011 Conference on Innovative Data Systems Research  
The database community has provided excellent frameworks for efficient querying and online transaction or analytical processing.  ...  In particular, techniques like probabilistic modelling and statistical inference may be necessary to be able to draw meaningful conclusions from the underlying data.  ...  Hence, DBrev constructs factor graphs in which the truth value of the triple is constrained by factors that relate it to variables quantifying the reliability of sources.  ... 
dblp:conf/cidr/KasneciGG11 fatcat:jfplj5lngzf5zop27k7z5qnghq

Symbolic Querying of Vector Spaces: Probabilistic Databases Meets Relational Embeddings [article]

Tal Friedman, Guy Van den Broeck
2020 arXiv   pre-print
We formalize a probabilistic database model with respect to which all queries are done.  ...  We propose unifying techniques from probabilistic databases and relational embedding models with the goal of performing complex queries on incomplete and uncertain data.  ...  an assumption about the way in which the tensor representing all triples factorizes.  ... 
arXiv:2002.10029v2 fatcat:6olbfnh34rfftbzkan3m25id2u

Database Foundations for Scalable RDF Processing [chapter]

Katja Hose, Ralf Schenkel, Martin Theobald, Gerhard Weikum
2011 Lecture Notes in Computer Science  
to billions of triples.  ...  We cover search engines as well as federated query processing, highlight differences to classic federated database systems, and discuss efficient techniques for distributed query processing in general  ...  the probabilistic database.  ... 
doi:10.1007/978-3-642-23032-5_4 fatcat:5owq3argizaj3epzu4yhuuxc6i

pSPARQL: A Querying Language for Probabilistic RDF Data

Hong Fang
2019 Complexity  
In this paper, we present a querying language framework for probabilistic RDF data (an important uncertain linked data), where each triple has a probability, called pSRARQL, built on SPARQL, recommended  ...  by W3C as a querying language for RDF databases. pSPARQL can support the full SPARQL and satisfies some important properties such as well-definedness, uniqueness, and some equivalences.  ...  Reference [14] presents a RESCAL-based approach to query processing in relational data via factorization.  ... 
doi:10.1155/2019/8258197 fatcat:6c6jyxqdjneerjgezwqclszh4i

Representing Tuple and Attribute Uncertainty in Probabilistic Databases

Prithviraj Sen, Amol Deshpande, Lise Getoor
2007 Seventh IEEE International Conference on Data Mining Workshops (ICDMW 2007)  
Building on existing probabilistic database work, we present a unifying framework which allows a flexible representation of correlated tuple and attribute level uncertainties.  ...  There has been a recent surge in work in probabilistic databases, propelled in large part by the huge increase in noisy data sources -sensor data, experimental data, data from uncurated sources, and many  ...  As opposed to query evaluation for traditional databases containing exact data, query evaluation for probabilistic databases requires that we calculate probabilities associated with result tuples present  ... 
doi:10.1109/icdmw.2007.11 dblp:conf/icdm/SenDG07 fatcat:dmxy2luohzdsrjo5ycsbeq6k4y

Keyword Query Expansion Paradigm Based on Recommendation and Interpretation in Relational Databases

Yingqi Wang, Nianbin Wang, Lianke Zhou
2017 Scientific Programming  
Due to the ambiguity and impreciseness of keyword query in relational databases, the research on keyword query expansion has attracted wide attention.  ...  Second, by using the translation algorithm of triples and construction algorithm of query subgraphs, query keywords are translated to query subgraphs with structural and semantic information.  ...  for every keyword and expands the query to a query list using probabilistic recommendation algorithm.  ... 
doi:10.1155/2017/7613026 fatcat:igrxbycdejekli4zl5rigk5wii

On Constrained Open-World Probabilistic Databases [article]

Tal Friedman, Guy Van den Broeck
2019 arXiv   pre-print
One approach is to use a probabilistic database, a model with strong assumptions that allow for efficiently answering many interesting queries.  ...  Recent work on open-world probabilistic databases strengthens the semantics of these probabilistic databases by discarding the assumption that any information not present in the data must be false.  ...  We determine this probability P max using a standard probabilistic database query algorithm, and fixing R to have entries 0.8 for some disjoint set of triples.  ... 
arXiv:1902.10677v2 fatcat:k4sytuw64jhc3n34h7tf7tkbhy

ArchimedesOne

Xiaofeng Zhou, Yang Chen, Daisy Zhe Wang
2016 Proceedings of the VLDB Endowment  
To address these challenges, we develop a probabilistic knowledge base system, ARCHIMEDESONE, by scaling up the knowledge expansion and statistical inference algorithms.  ...  by applying inference rules in batches using relational operations and query-driven inference by focusing computation on the query facts.  ...  Alin Dobra for the helpful discussions on query optimization.  ... 
doi:10.14778/3007263.3007284 fatcat:txierprif5e7djvqorulut6m3e

Relational Models [article]

Volker Tresp, Maximilian Nickel
2016 arXiv   pre-print
Relational models typically are based on probabilistic graphical models, e.g., Bayesian networks, Markov networks, or latent variable models.  ...  The theory of probabilistic databases focussed on the issues of complex query answering under a probabilistic model.  ...  Triple Graphs and Probabilistic Graphical Networks A triple database consists of binary relations represented as subject-predicateobject triples. An example of a triple is: (Jack, knows, Mary).  ... 
arXiv:1609.03145v1 fatcat:ytomwo4l5nfsrnpm2ens5iww6m

Learning a Compositional Semantics for Freebase with an Open Predicate Vocabulary

Jayant Krishnamurthy, Tom M. Mitchell
2015 Transactions of the Association for Computational Linguistics  
A training phase produces this probabilistic database using a corpus of entity-linked text and probabilistic matrix factorization with a novel ranking objective function.  ...  This logical form is evaluated against a learned probabilistic database that defines a distribution over denotations for each textual predicate.  ...  A training phase learns the probabilistic database by applying probabilistic matrix factorization with a query/answer ranking objective to logical forms derived from a large, entity-linked web corpus.  ... 
doi:10.1162/tacl_a_00137 fatcat:vuoo5747drfkdmjaa344kdli6q

Time-Aware Probabilistic Knowledge Graphs

Melisachew Wudage Chekol, Heiner Stuckenschmidt, Michael Wagner
2019 International Symposium/Workshop on Temporal Representation and Reasoning  
In this paper, we propose a bitemporal model (that combines transaction and valid time models) for maintaining and querying bitemporal probabilistic knowledge graphs.  ...  Moreover, we show that complexity of reasoning tasks in atemporal probabilistic KG carry over to the bitemporal setting. Finally, we report our evaluation results of the proposed model.  ...  Query evaluation in probabilistic databases is an active area of research [19, 7, 40, 12] .  ... 
doi:10.4230/lipics.time.2019.8 dblp:conf/time/ChekolS19 fatcat:2mkqavw5pvfwjeb3juamg7fu5q

Term dependence: Truncating the Bahadur Lazarsfeld expansion

Robert M. Losee
1994 Information Processing & Management  
The performance of probabilistic information retrieval systems is studied where differing statistical dependence assumptions are used when estimating the probabilities inherent in the retrieval model.  ...  The queries in the CF database are ordered by subject and thus the first group of queries can be treated as different than the second group, and so on [16] .  ...  The CF database contains 100 natural language queries, 1239 document abstracts, and exhaustive relevance judgements.  ... 
doi:10.1016/0306-4573(94)90071-x fatcat:p5hrsjw4uvgt7o3i4e5jljig4y

SPARQL basic graph pattern optimization using selectivity estimation

Markus Stocker, Andy Seaborne, Abraham Bernstein, Christoph Kiefer, Dave Reynolds
2008 Proceeding of the 17th international conference on World Wide Web - WWW '08  
The heuristics range from simple triple pattern variable counting to more sophisticated selectivity estimation techniques.  ...  The heuristics range from simple triple pattern variable counting to more sophisticated selectivity estimation techniques.  ...  Query optimization is a fundamental and crucial subtask of query execution in database management systems.  ... 
doi:10.1145/1367497.1367578 dblp:conf/www/StockerSBKR08 fatcat:53o7miyozve4fdjruk5l3i62qe

An ant colony optimisation approach for optimising SPARQL queries by reordering triple patterns

Elem Guzel Kalayci, Tahir Emre Kalayci, Derya Birant
2015 Information Systems  
This new method reorders the triple patterns using Ant Colony Optimisation (ACO) algorithms. Reordering the triple patterns is a way of decreasing the execution times of the SPARQL queries.  ...  The first contribution is the real-time optimisation of SPARQL query triple pattern orders using ACO algorithms, and the second contribution is the concrete implementation for the ARQ query engine, which  ...  Determining the order of the triple patterns is a key factor in optimising joins [25] ; thus, it is a key factor for decreasing the execution time of the queries.  ... 
doi:10.1016/j.is.2015.01.013 fatcat:sbikx2zl7zghjbs2fpcil4gzaq
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