Results 1  10
of
14
A Faster Algorithm for Betweenness Centrality
 Journal of Mathematical Sociology
, 2001
"... The betweenness centrality index is essential in the analysis of social networks, but costly to compute. Currently, the fastest known algorithms require #(n ) time and #(n ) space, where n is the number of actors in the network. ..."
Abstract

Cited by 554 (5 self)
 Add to MetaCart
(Show Context)
The betweenness centrality index is essential in the analysis of social networks, but costly to compute. Currently, the fastest known algorithms require #(n ) time and #(n ) space, where n is the number of actors in the network.
Faster Evaluation of ShortestPath Based Centrality Indices
, 2000
"... Centrality indices are an important tool in network analysis, and many of them are derived from the set of all shortest paths of the underlying graph. The socalled betweenness centrality index is essential for the analysis of social networks, but most costly to compute. Currently, the fastest known ..."
Abstract

Cited by 4 (0 self)
 Add to MetaCart
(Show Context)
Centrality indices are an important tool in network analysis, and many of them are derived from the set of all shortest paths of the underlying graph. The socalled betweenness centrality index is essential for the analysis of social networks, but most costly to compute. Currently, the fastest known algorithms require Theta(n³) time and Theta(n²) space, where n is the number of vertices. Motivated by the fastgrowing need to compute centrality indices on large, yet very sparse, networks, new algorithms for betweenness are introduced in this paper. They require O(n + m) space and run in O(n(m + n)) or O(n(m + n log n)) time on unweighted or weighted graphs, respectively, where m is the number of edges. Since these algorithms simply augment singlesource shortestpaths computations, all standard centrality indices based on shortest paths can now be computed uniformly in one framework. Experimental evidence is provided that this substantially increases the range of network...
Centrality in Social Networks
 Developments in Data Analysis
, 1996
"... Abstract In the paper an introduction to main social networks centrality measures is given. A new view on these measures is proposed, based on relational algebra. All described measures are implemented in computer programs CENTRAL and FLOWIND. ..."
Abstract

Cited by 2 (0 self)
 Add to MetaCart
(Show Context)
Abstract In the paper an introduction to main social networks centrality measures is given. A new view on these measures is proposed, based on relational algebra. All described measures are implemented in computer programs CENTRAL and FLOWIND.
Structural balance and partitioning signed graphs
 In A. Ferligoj & A. Kramberger (Eds.), Developments in data analysis (Metodoloski zvezki 12
, 1996
"... Abstract Signed graphs have been used frequently to model affect ties for social actors. In this context, structural balance theory has been used as a theory for the organization and form of these relations. Based on a graph theoretical formalization of this theory, for signed graphs, there are the ..."
Abstract

Cited by 2 (1 self)
 Add to MetaCart
Abstract Signed graphs have been used frequently to model affect ties for social actors. In this context, structural balance theory has been used as a theory for the organization and form of these relations. Based on a graph theoretical formalization of this theory, for signed graphs, there are theorems stating that balanced structures have clear partitioned forms. We discuss the use of local optimization procedures as a method of obtaining these partitioned structures or partitioned structures that are as close to a balanced partition as possible for structures that are not balanced. In addition, this method provides a measure of the extent to which a signed graph is imbalanced. For a time series of signed graphs, this permits a test of the balance hypothesis that human groups tend towards balance over time. Examples are provided of interpersonal ties in networks and institutionalized relations among collective units.
On anti fuzzy left hideals in hemirings
 International Mathematical Forum
, 2007
"... In this paper we apply the Biswas’s idea of anti fuzzy subgroups to left hideals of hemirings. We introduce the notion of anti fuzzy left hideals in hemirings and investigate some of related properties. Relationship between fuzzy left hideals and anti fuzzy left hideals of hemirings is also give ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
(Show Context)
In this paper we apply the Biswas’s idea of anti fuzzy subgroups to left hideals of hemirings. We introduce the notion of anti fuzzy left hideals in hemirings and investigate some of related properties. Relationship between fuzzy left hideals and anti fuzzy left hideals of hemirings is also given.
unknown title
, 2013
"... Optimizing protections against cascades in network systems: a modified binary differential evolution algorithm ..."
Abstract
 Add to MetaCart
Optimizing protections against cascades in network systems: a modified binary differential evolution algorithm
Network analysis of LRE metadata
"... Abstract. In the paper an approach to analysis of the structure of repositories based on network analysis is proposed. The repository metadata can be transformed into several (onemode or twomode) networks. Using the methods of network analysis interesting substructures in these networks can be de ..."
Abstract
 Add to MetaCart
Abstract. In the paper an approach to analysis of the structure of repositories based on network analysis is proposed. The repository metadata can be transformed into several (onemode or twomode) networks. Using the methods of network analysis interesting substructures in these networks can be detected. In the paper we present some results from network analyses of a large data set of LRE metadata (version May 2009) prepared in projects Calibrate and MELT, and collected from several European educational repositories by European Schoolnet.
GENERALIZED MATRIX MULTIPLICATION AND ITS OBJECT ORIENTED MODEL
"... Since the beginning of the 21st century, we observe rapid changes in the area of, broadly understood, computational sciences. One of interesting eects of these changes is the need for reevaluation of the role of dense matrix multiplication. The aim of this paper is twofold. First, to summarize deve ..."
Abstract
 Add to MetaCart
(Show Context)
Since the beginning of the 21st century, we observe rapid changes in the area of, broadly understood, computational sciences. One of interesting eects of these changes is the need for reevaluation of the role of dense matrix multiplication. The aim of this paper is twofold. First, to summarize developments that point toward a need for reconsidering usefulness of matrix multiplication generalized on the basis of the theory of algebraic semirings. Second, to propose generalized matrixmatrix multiplyandupdate (MMU) operation and its object oriented model. Key words: matrix multiplication, algebraic semirings, algebraic path problem AMS subject classications. 65F30, 13A99 1. Introduction. Recently