Results 91 to 100 of about 143,400 (232)
Rees algebras of complete bipartite graphs.
Matemática Contemporânea, 1999 To every graph one can associate an ideal \(I\) generated by the products of the pairs of variables of the edges. This paper studies the Rees algebra \(R(I)\) of the edge ideal of complete bipartite graphs. It gives a Gröbner basis for the defining ideal and then uses it to compute the Hilbert series of \(R(I)\).
openaire +2 more sources
Stratified sampling enhances the understanding of bat–fruit networks in the southern Atlantic Forest
Oikos, EarlyView.Few studies have sought to understand the vertical patterns of bat–fruit systems, and therefore, it is not possible to evaluate whether interpretations based on data collected from a single stratum adequately represent the interaction patterns of this system. In this context, we evaluated the dissimilarity in the assemblage of frugivorous bats, plants,
Karolaine Porto Supi +3 more
wiley +1 more source
The Bipartite-Splittance of a Bipartite Graph
Discussiones Mathematicae Graph Theory, 2019 A bipartite-split graph is a bipartite graph whose vertex set can be partitioned into a complete bipartite set and an independent set. The bipartite- splittance of an arbitrary bipartite graph is the minimum number of edges to be added or removed in ...
Yin Jian-Hua, Guan Jing-Xin
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Generating Compressed Counterfactual Hard Negative Samples for Graph Contrastive Learning
CAAI Transactions on Intelligence Technology, EarlyView.ABSTRACT Graph contrastive learning (GCL) relies on acquiring high‐quality positive and negative samples to learn the structural semantics of the input graph. Previous approaches typically sampled negative samples from the same training batch or an irrelevant external graph.
Haoran Yang +7 more
wiley +1 more source
Effects on Seidel energy of two special types of graphs by perturbing edges
Kuwait Journal of ScienceLet G be a simple undirected graph, and let S(G) be its Seidel matrix. The Seidel energy of G is defined as ES(G)=∑i=1n|λS(G)|, where λS(G),λS(G),…,λS(G) are Seidel eigenvalues of G.
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Extreme edge-friendly indices of complete bipartite graphs [PDF]
Transactions on Combinatorics, 2016 Let G=(V,E) be a simple graph. An edge labeling f:E to {0,1} induces a vertex labeling f^+:V to Z_2 defined by $f^+(v)equiv sumlimits_{uvin E} f(uv)pmod{2}$ for each $v in V$, where Z_2={0,1} is the additive group of order 2.
Wai Chee Shiu
doaj
Identifiability conditions in cognitive diagnosis: Implications for Q‐matrix estimation algorithms
British Journal of Mathematical and Statistical Psychology, EarlyView.Abstract The Q‐matrix of a cognitively diagnostic assessment (CDA), documenting the item‐attribute associations, is a key component of any CDA. However, the true Q‐matrix underlying a CDA is never known and must be estimated—typically by content experts.
Hyunjoo Kim +2 more
wiley +1 more source
Star-path and star-stripe bipartite Ramsey numbers in multicoloring [PDF]
Transactions on Combinatorics, 2015 For given bipartite graphs G 1 ,G 2 ,…,G t , the bipartite Ramsey number bR(G 1 ,G 2 ,…,G t ) is the smallest integer n such that if the edges of the complete bipartite graph K n,n are partitioned into t disjoint color classes giving t ...
Ghaffar Raeisi
doaj
The Entropy of Weighted Graphs with Atomic Bond Connectivity Edge Weights
Discrete Dynamics in Nature and Society, 2018 The aim of this report to solve the open problem suggested by Chen et al. We study the graph entropy with ABC edge weights and present bounds of it for connected graphs, regular graphs, complete bipartite graphs, chemical graphs, tree, unicyclic graphs ...
Young Chel Kwun +4 more
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Bipartite Ramsey numbers involving stars, stripes and trees
Electronic Journal of Graph Theory and Applications, 2013 The Ramsey number R(m, n) is the smallest integer p such that any blue-red colouring of the edges of the complete graph Kp forces the appearance of a blue Km or a red Kn.
Michalis Christou +2 more
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