Results 1 - 10 of 365,784

Maximum likelihood from incomplete data via the EM algorithm

by A. P. Dempster, N. M. Laird, D. B. Rubin - JOURNAL OF THE ROYAL STATISTICAL SOCIETY, SERIES B , 1977
"... A broadly applicable algorithm for computing maximum likelihood estimates from incomplete data is presented at various levels of generality. Theory showing the monotone behaviour of the likelihood and convergence of the algorithm is derived. Many examples are sketched, including missing value situat ..."
Abstract - Cited by 11972 (17 self) - Add to MetaCart
situations, applications to grouped, censored or truncated data, finite mixture models, variance component estimation, hyperparameter estimation, iteratively reweighted least squares and factor analysis.

The Logical Data Model

by Gabriel M. Kuper, Moshe Y. Vardi - ACM Transactions On Database Systems , 1997
"... We propose an object-oriented data model that generalizes the relational, hierarchical, and network models. A database scheme in this model is a directed graph, whose leaves represent data and whose internal nodes represent connections among the data. Instances are constructed from objects, which ha ..."
Abstract - Cited by 26 (0 self) - Add to MetaCart
;A new approach to database logic", appeared in Proc. 3rd ACM Symp. on Principles of Database Systems, Waterloo, April 1984, pp. 86-96. For a more extensive coverage of the material presented here the reader is referred to the first author's Ph.D. dissertation The logical data model: a new

On the Complexity of Queries in the Logical Data Model

by Gabriel M. Kuper, Moshe Y. Vardi - THEORETICAL COMPUTER SCIENCE , 1993
"... We investigate the complexity of query processing in the logical data model (LDM). We use two measures: data complexity, which is complexity with respect to the size of the data, and expression complexity, which is complexity with respect to the size of the expressions denoting the queries. Our inve ..."
Abstract - Cited by 19 (0 self) - Add to MetaCart
We investigate the complexity of query processing in the logical data model (LDM). We use two measures: data complexity, which is complexity with respect to the size of the data, and expression complexity, which is complexity with respect to the size of the expressions denoting the queries. Our

Logical Data Modeling: Part 1

by Terry Halpin
"... My previous fifteen articles on ontology-based approaches to data modeling focused on popular ontology languages for the Semantic Web, such as the Resource Description Framework (RDF), RDF Schema (RDFS), and the Web Ontology Language (OWL). While these languages may be used to specify a data model o ..."
Abstract - Cited by 2 (2 self) - Add to MetaCart
on an alternative, logic-based approach to business data and rules using a single language to both create and query data models.

Logical Data Modeling: Part 3

by Terry Halpin
"... This is the third article in a series on logic-based approaches to data modeling. The first article n-ary Fact Types with a Spanning Uniqueness Constraint Figure 1 depicts a simple data model for recording the sports in which various countries competed in various games of the summer Olympics of th ..."
Abstract - Cited by 1 (1 self) - Add to MetaCart
This is the third article in a series on logic-based approaches to data modeling. The first article n-ary Fact Types with a Spanning Uniqueness Constraint Figure 1 depicts a simple data model for recording the sports in which various countries competed in various games of the summer Olympics

Spatial Pictogram Enhanced Conceptual Data Models and Their Translation to Logical Data Models

by Shashi Shekhar, Ranga Raju Vatsavai, Thomas E. Burk - Integrated Spatial Databases, Digital Images, and GIS, Lecture Notes in Computer Science , 1999
"... Abstract. The successful development ofany geographic information system project needs the careful design and implementation of spatial databases via conceptual and logical data-modeling. This involves understanding the underlying spatial data model, spatial data types and operators, spatial query l ..."
Abstract - Cited by 7 (3 self) - Add to MetaCart
Abstract. The successful development ofany geographic information system project needs the careful design and implementation of spatial databases via conceptual and logical data-modeling. This involves understanding the underlying spatial data model, spatial data types and operators, spatial query

Separation Logic: A Logic for Shared Mutable Data Structures

by John Reynolds , 2002
"... In joint work with Peter O'Hearn and others, based on early ideas of Burstall, we have developed an extension of Hoare logic that permits reasoning about low-level imperative programs that use shared mutable data structure. ..."
Abstract - Cited by 950 (6 self) - Add to MetaCart
In joint work with Peter O'Hearn and others, based on early ideas of Burstall, we have developed an extension of Hoare logic that permits reasoning about low-level imperative programs that use shared mutable data structure.

The Stable Model Semantics For Logic Programming

by Michael Gelfond, Vladimir Lifschitz , 1988
"... We propose a new declarative semantics for logic programs with negation. Its formulation is quite simple; at the same time, it is more general than the iterated fixed point semantics for stratied programs, and is applicable to some useful programs that are not stratified. ..."
Abstract - Cited by 1847 (63 self) - Add to MetaCart
We propose a new declarative semantics for logic programs with negation. Its formulation is quite simple; at the same time, it is more general than the iterated fixed point semantics for stratied programs, and is applicable to some useful programs that are not stratified.

The Entity-Relationship Model: Toward a Unified View of Data

by Peter Pin-shan Chen - ACM Transactions on Database Systems , 1976
"... A data model, called the entity-relationship model, is proposed. This model incorporates some of the important semantic information about the real world. A special diagrammatic technique is introduced as a tool for database design. An example of database design and description using the model and th ..."
Abstract - Cited by 1829 (6 self) - Add to MetaCart
ambiguities in these models are analyzed. Possible ways to derive their views of data from the entity-relationship model are presented. Key Words and Phrases: database design, logical view of data, semantics of data, data models, entity-relationship model, relational model, Data Base Task Group, network model

Markov Logic Networks

by Matthew Richardson, Pedro Domingos - MACHINE LEARNING , 2006
"... We propose a simple approach to combining first-order logic and probabilistic graphical models in a single representation. A Markov logic network (MLN) is a first-order knowledge base with a weight attached to each formula (or clause). Together with a set of constants representing objects in the ..."
Abstract - Cited by 816 (39 self) - Add to MetaCart
We propose a simple approach to combining first-order logic and probabilistic graphical models in a single representation. A Markov logic network (MLN) is a first-order knowledge base with a weight attached to each formula (or clause). Together with a set of constants representing objects
Results 1 - 10 of 365,784