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A probabilistic relational model and algebra

Debabrata Dey, Sumit Sarkar
1996 ACM Transactions on Database Systems  
We present a revised relational structure and extend the relational algebra. The extended algebra ]s shown to be closed.  ...  Although the relational mode] for databases provides a great range of advantages over other data models, It lacks a comprehensive way to handle incomplete and uncertain data.  ...  and constructive criticisms.  ... 
doi:10.1145/232753.232796 fatcat:4oe2e2zadfgcnp5p7y6kejsfwu

A probabilistic relational database model and algebra

Hoa Nguyen
2015 Journal of Computer Science and Cybernetics  
In addition, a set of the properties of the probabilistic relational algebraic operations in PRDB also are formulated and proven.  ...  This paper introduces a probabilistic relational database model, called PRDB, for representing and querying uncertain information of objects in practice.  ...  Such models are called probabilistic relational database models [3] [4] [5] [6] . Some models were built by extending each classical relation to a probabilistic relation as in [7, 8] .  ... 
doi:10.15625/1813-9663/31/4/5742 fatcat:kxes7ypqdfflzlvij5gtuy7pc4

A FUZZY PROBABILISTIC RELATIONAL DATABASE MODEL AND ALGEBRA

Hòa Nguyễn
2016 Journal of Computer Science and Cybernetics  
A set of the properties of the relational algebraic operations in FPRDB is also formulated and proven.  ...  Then, schemas, fuzzy probabilistic relations, fuzzy probabilistic functional dependencies and algebraic operations are defined coherently and consistently for FPRDB.  ...  FPRDB is also a complete development for the model in [18] with a full set of basic fuzzy probabilistic relational algebraic operations.  ... 
doi:10.15625/1813-9663/32/2/7887 fatcat:hef4cl2rk5hw5jxnipdu73mheu

A probabilistic relational model for the integration of IR and databases

Norbert Fuhr
1993 Proceedings of the 16th annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '93  
In this paper, a probabilistic relational model is presented which combines relational algebra with probabilistic retrieval.  ...  Based on certain independence assumptions, the operators of the relational algebra are redefined such that the probabilistic algebra is a generalization of the standard relational algebra.  ...  E' Figure 1: Relations representing a document database Figure 2: Relations DB and IR figure 6.  ... 
doi:10.1145/160688.160754 dblp:conf/sigir/Fuhr93 fatcat:ltivbn5oabbflptj4n7x7jrtoe

Models for Incomplete and Probabilistic Information [chapter]

Todd J. Green, Val Tannen
2006 Lecture Notes in Computer Science  
We also introduce a new idea for the study of models that are not complete. Namely, we consider combining existing models with queries in various fragments of relational algebra.  ...  We go beyond the problem of individual tuples in query answers by defining closure under a query language for probabilistic models.  ...  We introduced the concept of algebraic completion and gave some results showing that extending weaker models by various fragments of the relational algebra yields complete models.  ... 
doi:10.1007/11896548_24 fatcat:rkhqtknfybdzhaqml6ecsmfgq4

Abstraction in Probabilistic Process Algebra [chapter]

S. Andova, J. C. M. Baeten
2001 Lecture Notes in Computer Science  
Motivation and main ideas In this work we treat the problem of abstraction in fully probabilistic process algebra and its semantics based on branching bisimulation.  ...  we introduce veri cation rules in fully probabilistic process algebra that arise rather in a natural way from the one de ned in standard process algebra.  ...  An equivalence relation R is a probabilistic branching bisimulation relation i :1. if (p; q) 2 R and p ; s then either i.  ... 
doi:10.1007/3-540-45319-9_15 fatcat:eu7ag2llovalhapszj7iwlug34

A probabilistic relational algebra for the integration of information retrieval and database systems

Norbert Fuhr, Thomas Rölleke
1997 ACM Transactions on Information Systems  
We present a probabilistic relational algebra (PRA) which is a generalization of standard relational algebra.  ...  With these features, PRA implements uncertainty and vagueness in combination with the relational model.  ...  DESCRIPTION OF THE ALGEBRA In the following, we first describe the concepts of a probabilistic relation and a probabilistic database, and then we define the operators of the probabilistic relational algebra  ... 
doi:10.1145/239041.239045 fatcat:dmfa4ouxcvebzd3ceedmnrzxf4

Axiomatization of trace semantics for stochastic nondeterministic processes

A. Parma, R. Segala
2004 First International Conference on the Quantitative Evaluation of Systems, 2004. QEST 2004. Proceedings.  
We give a complete axiomatization of trace distribution precongruence for probabilistic nondeterministic processes based on a process algebra that includes internal behavior and recursion.  ...  The axiomatization is given for two different semantics of the process algebra that are consistent with the alternating model of Hansson and the non-alternating model of Segala, respectively.  ...  We consider a process algebra with nondeterministic choice, probabilistic choice, and recursion, that is, an algebra that extends classical process algebras with just one new operator that models probability  ... 
doi:10.1109/qest.2004.1348043 dblp:conf/qest/ParmaS04 fatcat:qdpthwdklfhiph36qtctq3u3nu

A Framework for Management of Semistructured Probabilistic Data

Wenzhong Zhao, Alex Dekhtyar, Judy Goldsmith
2005 Journal of Intelligent Information Systems  
Subrahmanian for helpful comments and the students working in the Bayesian Advisor group for their input at various stages, and their fabulous energy.  ...  Instead of modeling uncertain information with relational models, Kornatzky and Shimony [13] developed a probabilistic object-oriented model to represent uncertain information based on a probabilistic  ...  They provided a closed form query algebra and first introduced the conditionalization operation in the context of a probabilistic model.  ... 
doi:10.1007/s10844-005-0197-8 fatcat:phcwbqonqbcyrhfy56ijslnypi

Probabilistic Concurrent Kleene Algebra

Annabelle McIver, Tahiry Rabehaja, Georg Struth
2013 Electronic Proceedings in Theoretical Computer Science  
The algebra yields a unified framework containing nondeterminism, concurrency and probability and is sound with respect to the set of probabilistic automata modulo probabilistic simulation.  ...  We use the resulting algebra to generalise the algebraic formulation of a variant of Jones' rely/guarantee calculus.  ...  The equivalence relation is based on weak simulation and we are mainly interested in the equational theory of this model and relate it to the axiomatisation of probabilistic and concurrent Kleene algebras  ... 
doi:10.4204/eptcs.117.7 fatcat:tnzjyxycqzfxhke2o5ivgwgjbm

On Query Algebras for Probabilistic Databases

Christoph Koch
2009 SIGMOD record  
As a core algebra, we present probabilistic world-set algebra (WSA), origi-  ...  This article proposes a core query algebra for probabilistic databases.  ...  Probabilistic Databases Informally, our model of probabilistic databases is the following. The schema of a probabilistic database is simply a relational database schema.  ... 
doi:10.1145/1519103.1519116 fatcat:ex2el4xphvdzdo6hjxvqgmgnne

Page 6069 of Mathematical Reviews Vol. , Issue 2002H [page]

2002 Mathematical Reviews  
Summary: “In this paper we give a relation-algebraic model of processes.  ...  Summary: “In this chapter, we adopt probabilistic transition sys- tems as a basic model for probabilistic processes, in which prob- abilistic and nondeterministic choices are independent concepts.  ... 

Operator Algebras and the Operational Semantics of Probabilistic Languages

Alessandra Di Pierro, Herbert Wiklicky
2006 Electronical Notes in Theoretical Computer Science  
We argue that C * -algebras, or more precisely Approximately Finite (or AF) algebras, provide a sufficiently rich mathematical structure for modelling probabilistic processes.  ...  We show how to construct for a given probabilistic language a unique AF algebra A and how to represent the operational semantics of processes within this framework: finite computations correspond directly  ...  We will show that probabilistic relations which are defined on (at most countable) infinite sets can be modelled via continuous linear operators, which represent the elements of a C * -algebra.  ... 
doi:10.1016/j.entcs.2006.04.029 fatcat:lzxcer3kgbdnvfwdrjsi5rv6py

Modelling retrieval models in a probabilistic relational algebra with a new operator: the relational Bayes

Thomas Roelleke, Hengzhi Wu, Jun Wang, Hany Azzam
2007 The VLDB journal  
The contributions of this paper include the specification of probabilistic SQL (PSQL) and probabilistic relational algebra (PRA), a new relational operator for probability estimation (the relational Bayes  ...  This paper presents a probabilistic relational modelling (implementation) of the major probabilistic retrieval models.  ...  The relational Bayes has been promoted and funded through the contributions of CLCUC (Combined London College University Challenge seed fund) and the technology transfer department of Queen Mary University  ... 
doi:10.1007/s00778-007-0073-y fatcat:qiexpftcfvgs7eonakx3xocb7e

Page 6289 of Mathematical Reviews Vol. , Issue 2003h [page]

2003 Mathematical Reviews  
We discuss and relate operational, denotational, algebraic and logical approaches to trace-oriented models and explain methods for the specification and verification of process behaviour based on these  ...  For example, in other probabilistic process algebras, bisimulation is treated in a non-probabilistic fashion, so that the following two processes are regarded as non-bisimular: [0.5]a.0 + [0.5]b.0 and  ... 
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