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On problems of databases over a fixed infinite universe

Oleg Belegradek, Alexei Stolboushkin, Michael Taitslin
1999 Banach Center Publications  
We further distinguish one broad class of ordered domains satisfying the Isolation Property, the so-called quasi-o-minimal domains.  ...  We provide very general conditions on the FO theory of an ordered domain that ensure collapse of order-generic extended FO queries to pure order queries over this domain: the Pseudofinite Homogeneity Property  ...  By Theorem 3.24, every o -minimal theory is quasi-o -minimal.  ... 
doi:10.4064/-46-1-23-62 fatcat:axt746x7pzbgpirsymwyktt6f4

Distribution based microdata anonymization

Nick Koudas, Divesh Srivastava, Ting Yu, Qing Zhang
2009 Proceedings of the VLDB Endowment  
We identify metrics related to accuracy of aggregate query answers over the transformed data, and develop efficient anonymization algorithms to optimize these accuracy metrics.  ...  To support such models, in this paper we study the problem of transforming a group of sensitive attribute values to follow a certain target distribution with minimal data distortion.  ...  Samarati also designed a binary search algorithm to identify minimal quasi-identifier domain generalizations.  ... 
doi:10.14778/1687627.1687735 fatcat:ljj5pww4inevdibgwauulhdhke

First-Order Queries over One Unary Function [chapter]

Arnaud Durand, Frédéric Olive
2006 Lecture Notes in Computer Science  
Also, since a forest of (colored) unranked tree is a quasi-unary structure, all our results apply immediately to queries over that later kind of structures.  ...  Finally, we investigate the special case of conjunctive queries over quasiunary structures and show that their combined complexity is not prohibitive, even from a dynamical (enumeration) point of view.  ...  Boolean) FO-query over a quasi-unary signature linearly reduces to a FO 0 -query (resp. FO 1 -query) over a quasi-unary signature. Proof.  ... 
doi:10.1007/11874683_22 fatcat:pmwb5lv75reinppoc455yxl3pe

Using SPARQL to Test for Lattices: Application to Quality Assurance in Biomedical Ontologies [chapter]

Guo-Qiang Zhang, Olivier Bodenreider
2010 Lecture Notes in Computer Science  
Our experimental results have been groundbreaking: for the first time, all non-lattice pairs in SNOMED CT have been identified exhaustively from 34 million candidate pairs using over 2.5 billion queries  ...  These non-lattice pairs represent target areas for focused curation by domain experts.  ...  Over 1.6 billion queries were issued to Virtuoso for testing the probes.  ... 
doi:10.1007/978-3-642-17749-1_18 pmid:25699294 pmcid:PMC4330995 fatcat:srdrq2xsmff53bgw3cmugzbyxe

Page 6547 of Mathematical Reviews Vol. , Issue 2000i [page]

2000 Mathematical Reviews  
We further distinguish one broad class of domains satisfying the isolation property, the so-called quasi-o-minimal domains.  ...  This class in- cludes not only all the o-minimal domains, but also the ordered group of integer numbers and the ordered semigroup of natural numbers, and some other domains.  ... 

Aggregate Query Answering on Anonymized Tables

Qing Zhang, Nick Koudas, Divesh Srivastava, Ting Yu
2007 2007 IEEE 23rd International Conference on Data Engineering  
aggregate queries more accurately than generalization-based approaches.  ...  Existing generalization-based anonymization approaches cannot answer aggregate queries with reasonable accuracy.  ...  through domain generalization.  ... 
doi:10.1109/icde.2007.367857 dblp:conf/icde/ZhangKSY07 fatcat:k45k6r2gpjcnrgjvj3rgtbxnze

The complexity of querying indefinite data about linearly ordered domains

R. van der Meyden
1992 Proceedings of the eleventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems - PODS '92  
In applications dealing with ordered domains, the available data is frequently indefinite.  ...  While the domain is actually linearly ordered, only some of the order relations holding between points in the data are known.  ...  The following result generalizes the fact that the subword relation is a well-quasi-order. Lemma 6.3. The relation P well-quasi-orders the set of flexi-words over a finite set Pred. Proof.  ... 
doi:10.1145/137097.137902 dblp:conf/pods/Meyden92 fatcat:2jt776uscbasthpc3so5wzqmnu

The Complexity of Querying Indefinite Data about Linearly Ordered Domains

Ron van der Meyden
1997 Journal of computer and system sciences (Print)  
In applications dealing with ordered domains, the available data is frequently indefinite.  ...  While the domain is actually linearly ordered, only some of the order relations holding between points in the data are known.  ...  The following result generalizes the fact that the subword relation is a well-quasi-order. Lemma 6.3. The relation P well-quasi-orders the set of flexi-words over a finite set Pred. Proof.  ... 
doi:10.1006/jcss.1997.1455 fatcat:ivf7ji653jfajijbhthhwje3nq

Efficiently Supporting Online Privacy-Preserving Data Publishing in a Distributed Computing Environment

Jong Kim
2021 Applied Sciences  
In particular, given a user's query, the proposed approach effectively estimates the generalization level of each quasi-identifier attribute, thereby achieving the k-anonymity property in the query result  ...  Thus, we developed a novel scheme that is able to efficiently anonymize the query results on the fly, and thus support efficient online privacy-preserving data publishing.  ...  A generalization lattice over attribute domain generalization hierarchies is constructed using a set of all possible combinations of the generalization levels of each attribute (Figure 3 ).  ... 
doi:10.3390/app112210740 fatcat:miggrtotqrg47fba7sbf73u32m

Mondrian Multidimensional K-Anonymity

K. LeFevre, D.J. DeWitt, R. Ramakrishnan
2006 22nd International Conference on Data Engineering (ICDE'06)  
Often this flexibility leads to higher-quality anonymizations, as measured both by general-purpose metrics and more specific notions of query answerability.  ...  A global recoding achieves anonymity by mapping the domains of the quasi-identifier attributes to generalized or altered values [17] .  ...  Thus, S is a minimal single-dimensional partitioning, and the size of the largest resulting region is O(|P |).  ... 
doi:10.1109/icde.2006.101 dblp:conf/icde/LeFevreDR06 fatcat:qjczv3kngnbvxot7m7xaybhcsa

Reasoning with examples: propositional formulae and database dependencies

Roni Khardon, Heikki Mannila, Dan Roth
1999 Acta Informatica  
validity of certain queries on the domain.  ...  Then the size of the minimal Armstrong relation of , with respect to queries which are either FDs or (k; q)-BDDs, is O(p 1 (n) jDNF(f )j), where p 1 (n) = O(n 3 + n k ).  ... 
doi:10.1007/s002360050161 fatcat:rc6yrxwwazbarmvq4obu65ndzm


Kristen LeFevre, David J. DeWitt, Raghu Ramakrishnan
2005 Proceedings of the 2005 ACM SIGMOD international conference on Management of data - SIGMOD '05  
We introduce a set of algorithms for producing minimal full-domain generalizations, and show that these algorithms perform up to an order of magnitude faster than previous algorithms on two real-life databases  ...  Besides full-domain generalization, numerous other models have also been proposed for k-anonymization.  ...  We implemented the k-anonymity check as a group-by query over the star schema.  ... 
doi:10.1145/1066157.1066164 dblp:conf/sigmod/LeFevreDR05 fatcat:tr4mgn7pajc7bbydnuomix5sk4

K-Anonymization as Spatial Indexing: Toward Scalable and Incremental Anonymization

Tochukwu Iwuchukwu, David J. DeWitt, AnHai Doan, Jeffrey F. Naughton
2007 2007 IEEE 23rd International Conference on Data Engineering  
properties of R-trees generate anonymizations superior to those generated by previously proposed anonymization algorithms.  ...  We use this observation to leverage over 20 years of work on database indexing to provide efficient and dynamic anonymization techniques.  ...  This enables us to anonymize a data set of 100,000,000 records. • We observe that minimal bounding boxes from the indexing domain [5, 10, 27] suggest anonymizations that leave gaps in the domain.  ... 
doi:10.1109/icde.2007.369024 dblp:conf/icde/IwuchukwuDDN07 fatcat:semsw5i2gfhvnjanzp66bl7syi

Theory of Privacy and Anonymity [chapter]

Valentina Ciriani, Sabrina Vimercati, Sara Foresti, Pierangela Samarati
2009 Algorithms and Theory of Computation Handbook, Second Edition, Volume 2  
Incognito The Incognito algorithm [29] has been proposed for computing a k-minimal generalization by using a domain generalization hierarchy DGH DT on the domain tuple of the quasi-identifier, where  ...  Note that a locally minimal generalization may not correspond to a k-minimal generalization, since a generalization may be locally minimal along one path but not along another one.  ... 
doi:10.1201/9781584888215-c18 fatcat:kzotla2k5nfgdlj4p2lz4scpgu

Learning conditional preference networks

Frédéric Koriche, Bruno Zanuttini
2010 Artificial Intelligence  
In a nutshell, our results reveal that active queries are required for efficiently learning CP-nets in large multi-attribute domains.  ...  Our learning algorithms are shown to be quasi-optimal by deriving lower bounds on the VC-dimension of CP-nets.  ...  A membership query MQ over I takes an example (o, o ) ∈ I n and returns Yes if o o , and No otherwise. 1 An equivalence query EQ over I takes a CP-net N ∈ N n , and returns Yes if N is a representation  ... 
doi:10.1016/j.artint.2010.04.019 fatcat:7dxbp43ndbhrhdxrai54ir5mja
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