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New Approximation Algorithms for Forest Closeness Centrality – for Individual Vertices and Vertex Groups [article]

Alexander van der Grinten, Eugenio Angriman, Maria Predari, Henning Meyerhenke
2021 arXiv   pre-print
Our method exploits the strong connection between uniform spanning trees and forest distances by adapting and extending recent approximation algorithms for related single-vertex problems.  ...  Moreover, our experiments show that on disconnected graphs, group forest closeness outperforms existing centrality measures in the context of semi-supervised vertex classification.  ...  Forest Farness Approximation Algorithm. As mentioned, our new algorithm for forest closeness exploits previous algorithmic results for approximating diag(L G † ) and electrical closeness.  ... 
arXiv:2101.06192v1 fatcat:v7ks2xvembdcxhr735xehmpbde

A polynomial-time approximation to optimal multivariate microaggregation

Josep Domingo-Ferrer, Francesc Sebé, Agusti Solanas
2008 Computers and Mathematics with Applications  
criteria: minimum within-groups Euclidean distance and minimum within-groups sum of squares.  ...  Microaggregation is a family of methods for statistical disclosure control (SDC) of microdata (records on individuals and/or companies), that is, for masking microdata so that they can be released without  ...  Basically, FOREST is a loop where each iteration adds a new edge linking two vertices.  ... 
doi:10.1016/j.camwa.2007.04.034 fatcat:2udxsymkw5bodotznu5fjtqqfa

Using Graph and Vertex Entropy to Compare Empirical Graphs with Theoretical Graph Models

Tomasz Kajdanowicz, Mikołaj Morzy
2016 Entropy  
Therefore, we propose a new method for graph comparison and type classification by comparing the entropies of centrality measure distributions (degree centrality, betweenness centrality, closeness centrality  ...  However, this approach is both error-prone and leads to incorrect conclusions, as we show in our experiments.  ...  In future we intend to examine a large spectrum of real-world networks and employ both supervised and unsupervised algorithms to group them.  ... 
doi:10.3390/e18090320 fatcat:tdrmo2mcgvf2bbsbvvwznbpbxi

Experimental Comparison of Semantic Word Clouds [chapter]

Lukas Barth, Stephen G. Kobourov, Sergey Pupyrev
2014 Lecture Notes in Computer Science  
We implement three earlier algorithms for creating word clouds and three new ones. We define several metrics for quantitative evaluation of the resulting layouts.  ...  Then the algorithms are compared according to these metrics, using two data sets of documents from Wikipedia and research papers.  ...  Further acknowledgements go to Jixiang Li, Jiankun Lu, and Zixiang Zhou for their help with the implementation of the semantic word cloud online tool, http://wordcloud.cs.arizona.edu.  ... 
doi:10.1007/978-3-319-07959-2_21 fatcat:5jzandfedjdbhcsw2s4tdxgqfe

Priority Attachment: a Comprehensive Mechanism for Generating Networks

Mikołaj Morzy, Tomasz Kajdanowicz, Przemysław Kazienko, Grzegorz Miebs, Arkadiusz Rusin
2019 Scientific Reports  
We introduce a simple model, which uses the priority attachment to generate both synthetic and close to empirical networks.  ...  We substantiate our claims by performing numerical experiments on both synthetic and empirical networks.  ...  Acknowledgments We wish to thank F.Menczer, S.Fortunato, and A.Flammini for their valuable remarks.  ... 
doi:10.1038/s41598-019-40015-9 pmid:30833611 pmcid:PMC6399255 fatcat:nvwksrtmsfgnfl7ipa7fongne4

Computing the Hybridization Number of Two Phylogenetic Trees Is Fixed-Parameter Tractable

M. Bordewich, C. Semple
2007 IEEE/ACM Transactions on Computational Biology & Bioinformatics  
Despite the existence of reticulation, such events are relatively rare and so a fundamental problem for biologists is the following: given a collection of rooted binary phylogenetic trees on sets of species  ...  Reticulation processes in evolution mean that the ancestral history of certain groups of present-day species is non-tree-like.  ...  First, the vertex set of G F ′ is obtained from G F by deleting the vertices T j for all j ∈ J, and introducing the new vertex T a .  ... 
doi:10.1109/tcbb.2007.1019 pmid:17666765 fatcat:2z6ny3tyyzezxbxqajso2jly7i

The pursuit of a good possible world

Panos Parchas, Francesco Gullo, Dimitris Papadias, Franceseco Bonchi
2014 Proceedings of the 2014 ACM SIGMOD international conference on Management of data - SIGMOD '14  
such as shortest path distance, clustering coefficient and betweenness centrality.  ...  Specifically, our algorithms aim at preserving the expected vertex degrees because they capture well the graph topology.  ...  Acknowledgements Panos Parchas and Dimitris Papadias were supported by grant HKUST 6177/13 from Hong Kong RGC.  ... 
doi:10.1145/2588555.2593668 dblp:conf/sigmod/ParchasGPB14 fatcat:34vn4yde6nfglcndiciq72opju

Static and Dynamic Community Detection Methods that Optimize a Specific Objective Function: A Survey and Experimental Evaluation

Kamal Taha
2020 IEEE Access  
We survey in this paper all fine-grained community detection categories, the clustering methods that fall under these categories, and the techniques employed by these methods for optimizing each objective  ...  In summary, the blockbased, top-down divisive-based, random walk-based, and matrix eigenvector-based methods achieved good results. Finally, we provide fitness metrics for each objective function.  ...  For maximizing the internal density objective function, the hierarchy centric, group centric, and vertex centric clustering categories achieved close results when the fraction of revealed vertices was  ... 
doi:10.1109/access.2020.2996595 fatcat:lf6ghd6afjhi7cls4vnutoytlu

Forest Fire Clustering for Single-cell Sequencing with Iterative Label Propagation and Parallelized Monte Carlo Simulation [article]

Zhanlin Chen, Jeremy Goldwasser, Philip Tuckman, Jason Liu, Jing Zhang, Mark Gerstein
2022 arXiv   pre-print
Here, we introduce Forest Fire Clustering, an efficient and interpretable method for cell-type discovery from single-cell data.  ...  Overall, Forest Fire Clustering is a useful tool for rare cell type discovery in large-scale single-cell analysis.  ...  Acknowledgments Research reported in this publication was supported by the National Institutes of Health under award numbers K01MH123896, U01DA053628, and UM1DA051410.  ... 
arXiv:2103.11802v4 fatcat:lhmjndie5bffzk6jhnyb3jddbm

The Spanning Tree based Approach for Solving the Shortest Path Problem in Social Graphs

Andrei Eremeev, Georgiy Korneev, Alexander Semenov, Jari Veijalainen
2016 Proceedings of the 12th International Conference on Web Information Systems and Technologies  
This paper describes an efficient shortest path searching algorithm suitable for large social graphs. The described algorithm extends the Atlas algorithm.  ...  There are many shortest path algorithms, but the majority of them suits only for small graphs, or work only with road network graphs that are fundamentally different from social graphs.  ...  These problems involve calculations of such metrics as betweenness centrality, closeness centrality, harmonic centrality and others.  ... 
doi:10.5220/0005859400420053 dblp:conf/webist/EremeevKSV16 fatcat:lt6fxphsubhx3fl6tdjjwkp3em

Compact graph representations and parallel connectivity algorithms for massive dynamic network analysis

K. Madduri, D.A. Bader
2009 2009 IEEE International Symposium on Parallel & Distributed Processing  
We present new data structures to represent dynamic interaction networks, and discuss algorithms for processing parallel insertions and deletions of edges in small-world networks.  ...  insertions and deletions to a small-world network of 33.5 million vertices and 268 million edges.  ...  Well-known quantitative metrics for computing centrality are closeness, stress, and betweenness.  ... 
doi:10.1109/ipdps.2009.5161060 dblp:conf/ipps/MadduriB09 fatcat:zmhf354mznharab6dkuzqrj55q

Group betweenness and co-betweenness: Inter-related notions of coalition centrality

Eric D. Kolaczyk, David B. Chua, Marc Barthélemy
2009 Social Networks  
vertices in the group, and (ii) the co-betweenness of pairs of these vertices.  ...  Two natural ways to extend vertex betweenness centrality to sets of vertices are (i) in terms of geodesic paths that pass through at least one of the vertices in the set, and (ii) in terms of geodesic  ...  The standard betweenness centrality is defined with respect to individual vertices.  ... 
doi:10.1016/j.socnet.2009.02.003 fatcat:vwmdeh4m7fgatgsm24b23d6cgy

Liquidity in Credit Networks with Constrained Agents [article]

Geoffrey Ramseyer, Ashish Goel, David Mazieres
2020 arXiv   pre-print
Credit Networks capture many aspects of traditional currencies as well as new virtual currencies and payment mechanisms.  ...  An idealized payment network behaves like a Credit Network, a model for transactions across a network of bilateral trust relationships.  ...  Let n be the number of external vertices, and let G i be the star graph consisting of only the central vertex and the first i vertices.  ... 
arXiv:1910.02194v2 fatcat:3mn55i3xofe2fn3bnoarqhg3hu

BioCode: A Data-Driven Procedure to Learn the Growth of Biological Networks [article]

Emre Sefer
2021 arXiv   pre-print
However, we should frequently keep developing new models to better fit and explain the observed network features while new networks are being observed.  ...  We combine such instruction-wise representation with a genetic algorithm based optimization procedure to encode models for various biological networks.  ...  We design Algorithm 2 in BIOCODE which approximates the DMC model quite closely. Algorithm 2 introduces the DMC model coded in BIOCODE that is somewhat different than the one proposed by Vazquez et al  ... 
arXiv:2108.04776v2 fatcat:uzzd4r5e6vh5xiauiprpfwqczi

Parallel Batch-Dynamic Algorithms for k-Core Decomposition and Related Graph Problems [article]

Quanquan C. Liu, Jessica Shi, Shangdi Yu, Laxman Dhulipala, Julian Shun
2022 arXiv   pre-print
Our framework obtains new provably-efficient parallel batch-dynamic algorithms for maximal matching, clique counting, and vertex coloring.  ...  Given a graph with n vertices and a batch of updates ℬ, our algorithm provably maintains a (2 + ε)-approximation of the coreness values of all vertices (for any constant ε > 0) in O(|ℬ|log^2 n) amortized  ...  Applications Driving Architectures (ADA) Research Center, a JUMP Center co-sponsored by SRC and DARPA.  ... 
arXiv:2106.03824v2 fatcat:scqhtx6oyncqlo6oaewpy7zgka
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