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Related papers: The GFB Tree and Tree Imbalance Indices

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Tree-structured data naturally appear in various fields, particularly in biology where plants and blood vessels may be described by trees, but also in computer science because XML documents form a tree structure. This paper is devoted to…

Statistics Theory · Mathematics 2019-04-09 Romain Azaïs , Alexandre Genadot , Benoît Henry

Phylogenetic networks generalise phylogenetic trees and allow for the accurate representation of the evolutionary history of a set of present-day species whose past includes reticulate events such as hybridisation and lateral gene transfer.…

Populations and Evolution · Quantitative Biology 2018-09-05 Joan Carles Pons , Charles Semple , Mike Steel

Null models of binary phylogenetic trees are useful for testing hypotheses on real world phylogenies. In this paper we consider phylogenies as binary trees without edge lengths together with a sampling measure and encode them as algebraic…

Probability · Mathematics 2020-06-17 Josué Nussbaumer , Anita Winter

We prove that if every subgraph of a graph $G$ has a balanced separation of order at most $a$ then $G$ has treewidth at most $15a$. This establishes a linear dependence between the treewidth and the separation number.

Combinatorics · Mathematics 2018-12-21 Zdenek Dvorak , Sergey Norin

Much of the information about the multi-valley structure of disordered spin systems can be convened in a simple tree structure -- a barrier tree -- the leaves and internal nodes of which represent, respectively, the local minima and the…

Disordered Systems and Neural Networks · Physics 2009-11-10 Wim Hordijk , Jose F. Fontanari , Peter F. Stadler

We provide a complete description of possible covariance matrices consistent with a Gaussian latent tree model for any tree. We then present techniques for utilising these constraints to assess whether observed data is compatible with that…

Methodology · Statistics 2016-04-13 Nathaniel Shiers , Piotr Zwiernik , John A. D. Aston , Jim Q. Smith

One of the main applications of balance indices is in tests of null models of evolutionary processes. The knowledge of an exact formula for a statistic of a balance index, holding for any number n of leaves, is necessary in order to use…

Populations and Evolution · Quantitative Biology 2012-10-22 Gabriel Cardona , Arnau Mir , Francesc Rossello

In this paper we investigate an extremal problem on binary phylogenetic trees. Given two such trees $T_1$ and $T_2$, both with leaf-set ${1,2,...,n}$, we are interested in the size of the largest subset $S \subseteq {1,2,...,n}$ of leaves…

Combinatorics · Mathematics 2013-02-21 Daniel M. Martin , Bhalchandra D. Thatte

Rooted bifurcating trees are mathematical objects used to model evolutionary relationships and arise naturally in both coalescent theory and phylogenetics. Recent numerical representations of tree topologies, known as F-matrices, allow for…

Rooted binary perfect phylogenies provide a generalization of rooted binary unlabeled trees in which each leaf is assigned a positive integer value that corresponds in a biological setting to the count of the number of indistinguishable…

Populations and Evolution · Quantitative Biology 2024-10-22 Chloe E. Shiff , Noah A. Rosenberg

Nonlinear metrics, such as the F1-score, Matthews correlation coefficient, and Fowlkes-Mallows index, are often used to evaluate the performance of machine learning models, in particular, when facing imbalanced datasets that contain more…

Machine Learning · Computer Science 2022-06-30 Emir Demirović , Peter J. Stuckey

Index structures are one of the most important tools that DBAs leverage to improve the performance of analytics and transactional workloads. However, building several indexes over large datasets can often become prohibitive and consume…

Databases · Computer Science 2020-03-26 Alex Galakatos , Michael Markovitch , Carsten Binnig , Rodrigo Fonseca , Tim Kraska

The reconstruction of a central tendency `species tree' from a large number of conflicting gene trees is a central problem in systematic biology. Moreover, it becomes particularly problematic when taxon coverage is patchy, so that not all…

Populations and Evolution · Quantitative Biology 2014-05-27 Mike Steel , Joel D. Velasco

We study the statistics of height and balanced height in the binary search tree problem in computer science. The search tree problem is first mapped to a fragmentation problem which is then further mapped to a modified directed polymer…

Statistical Mechanics · Physics 2009-11-07 Satya N. Majumdar , P. L. Krapivsky

We introduce a cluster evaluation technique called Tree Index. Our Tree Index algorithm aims at describing the structural information of the clustering rather than the quantitative format of cluster-quality indexes (where the representation…

Machine Learning · Computer Science 2020-03-25 A. H. Beg , Md Zahidul Islam , Vladimir Estivill-Castro

We investigate the tractability of a simple fusion of two fundamental structures on graphs, a spanning tree and a perfect matching. Specifically, we consider the following problem: given an edge-weighted graph, find a minimum-weight…

Data Structures and Algorithms · Computer Science 2024-07-12 Kristóf Bérczi , Tamás Király , Yusuke Kobayashi , Yutaro Yamaguchi , Yu Yokoi

Errors might not have the same consequences depending on the task at hand. Nevertheless, there is limited research investigating the impact of imbalance in the contribution of different features in an error vector. Therefore, we propose the…

Machine Learning · Computer Science 2022-07-12 Xavier F. Cadet , Sara Ahmadi-Abhari , Hamed Haddadi

Among many topological indices of trees the sum of distances $\sigma(T)$ and the number of subtrees $F(T)$ have been a long standing pair of graph invariants that are well known for their negative correlation. That is, among various given…

Combinatorics · Mathematics 2017-12-05 Shuchao Li , Hua Wang , Shujing Wang

Planning for the protection of species often involves difficult choices about which species to prioritize, given constrained resources. One way of prioritizing species is to consider their "evolutionary distinctiveness", i.e. their relative…

Populations and Evolution · Quantitative Biology 2021-07-05 Mareike Fischer , Andrew Francis , Kristina Wicke

We present a method that maintains a balanced binary search tree without using any tree balance criterion at all, with the ultimate aim of maximum simplicity. In fact, our method is highly intuitive, and we only need to add minimal extra…

Data Structures and Algorithms · Computer Science 2019-08-09 Tae Woo Kim