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Related papers: On the Optimal Shape of Tree Roots and Branches

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We consider problems in which we are given a rooted tree as input, and must find a subtree with the same root, optimizing some objective function of the nodes in the subtree. When this function is the sum of constant node weights, the…

Computational Geometry · Computer Science 2007-05-23 Josiah Carlson , David Eppstein

We provide time- and sample-efficient algorithms for learning and testing latent-tree Ising models, i.e. Ising models that may only be observed at their leaf nodes. On the learning side, we obtain efficient algorithms for learning a…

Machine Learning · Computer Science 2023-07-11 Davin Choo , Yuval Dagan , Constantinos Daskalakis , Anthimos Vardis Kandiros

We study optimal transport (OT) problem for probability measures supported on a tree metric space. It is known that such OT problem (i.e., tree-Wasserstein (TW)) admits a closed-form expression, but depends fundamentally on the underlying…

Machine Learning · Statistics 2024-03-04 Tam Le , Truyen Nguyen , Kenji Fukumizu

Plants have developed different tropisms: in particular, they re-orient the growth of their branches towards light (phototropism) or upwards (gravitropism). How these tropisms affect the shape of a tree crown remains unanswered. We address…

Biological Physics · Physics 2018-06-19 L. Duchemin , C. Eloy , E. Badel , B. Moulia

We present efficient algorithms for computing a maximum agreement forest (MAF) of a pair of multifurcating (nonbinary) rooted trees. Our algorithms match the running times of the currently best algorithms for the binary case. The size of an…

Data Structures and Algorithms · Computer Science 2013-05-03 Chris Whidden , Robert G. Beiko , Norbert Zeh

We study optimal two-sector (vegetative and reproductive) allocation models of annual plants in temporally variable environments, that incorporate effects of density dependent lifetime variability and juvenile mortality in a fitness…

Populations and Evolution · Quantitative Biology 2022-06-24 Sergiy Koshkin , Zachary Zalles , Michael F. Tobin , Nicolas Toumbacaris , Cameron Spiess

Given a graph $G=(V,E)$ with non-negative real edge lengths and an integer parameter $k$, the Min-Max k-Tree Cover problem seeks to find a set of at most $k$ subtrees of $G$, such that the union of the trees is the vertex set $V$. The…

Data Structures and Algorithms · Computer Science 2019-12-13 Syamantak Das , Lavina Jain , Nikhil Kumar

Let $T$ be a weighted tree. The weight of a subtree $T_1$ of $T$ is defined as the product of weights of vertices and edges of $T_1$. We obtain a linear-time algorithm to count the sum of weights of subtrees of $T$. As applications, we…

Combinatorics · Mathematics 2007-05-23 Weigen Yan , Yeong-Nan Yeh

We prove that finding a rooted subtree with at least $k$ leaves in a digraph is a fixed parameter tractable problem. A similar result holds for finding rooted spanning trees with many leaves in digraphs from a wide family $\cal L$ that…

Data Structures and Algorithms · Computer Science 2007-05-23 Noga Alon , Fedor Fomin , Gregory Gutin , Michael Krivelevich , Saket Saurabh

We present a general method for obtaining strong bounds for discrete optimization problems that is based on a concept of branching duality. It can be applied when no useful integer programming model is available, and we illustrate this with…

Data Structures and Algorithms · Computer Science 2019-08-22 J. G. Benade , J. N. Hooker

Compact and I/O-efficient data representations play an important role in efficient algorithm design, as memory bandwidth and latency can present a significant performance bottleneck, slowing the computation by orders of magnitude. While…

Data Structures and Algorithms · Computer Science 2018-11-19 Tomáš Gavenčiak , Jakub Tětek

In this paper we investigate the asymptotic optimality property of a randomized sampling based motion planner, namely RRT. We prove that a RRT planner is not an asymptotically optimal motion planner. Our result, while being consistent with…

Robotics · Computer Science 2017-07-14 Titas Bera , Debasish Ghose , Sundaram Suresh

Connected acyclic graphs (trees) are data objects that hierarchically organize categories. Collections of trees arise in a diverse variety of fields, including evolutionary biology, public health, machine learning, social sciences and…

Methodology · Statistics 2025-12-01 Maria Alejandra Valdez Cabrera , Amy D Willis , Armeen Taeb

Biology presents many examples of planar distribution and structural networks having dense sets of closed loops. An archetype of this form of network organization is the vasculature of dicotyledonous leaves, which showcases a…

Quantitative Methods · Quantitative Biology 2015-05-30 Eleni Katifori , Marcelo O. Magnasco

This work builds on the notion of record of rooted trees. We provide an alternative definition of parking functions, derive from it a record-preserving bijection between rooted trees and parking functions, and establish a join…

Combinatorics · Mathematics 2026-03-31 Adrián Lillo , Mercedes Rosas , Stefan Trandafir

Biological transport networks are highly optimized structures that ensure power-efficient distribution of fluids across various domains, including animal vasculature and plant venation. Theoretically, these networks can be described as…

Biological Physics · Physics 2025-08-01 Albert Alonso , Lars Erik J. Skjegstad , Julius B. Kirkegaard

We perform factorization of the most general distribution in semileptonic B -> X_u decays and we resum the threshold logarithms to next-to-leading order. From this (triple-differential) distribution, any other distribution is obtained by…

High Energy Physics - Phenomenology · Physics 2009-11-07 U. Aglietti

Region-based methods have proven necessary for improving segmentation accuracy of neuronal structures in electron microscopy (EM) images. Most region-based segmentation methods use a scoring function to determine region merging. Such…

Computer Vision and Pattern Recognition · Computer Science 2018-04-04 Ting Liu , Miaomiao Zhang , Mehran Javanmardi , Nisha Ramesh , Tolga Tasdizen

In this paper we consider the multiscale modelling of water transport in vegetated soil. In the microscopic model we distinguish between subdomains of soil and plant tissue, and use the Richards equation to model the water transport through…

Analysis of PDEs · Mathematics 2024-11-05 Andrew Mair , Mariya Ptashnyk

In this paper we present novel algorithmic techniques with a O(H(N)+N/H(N)) time complexity for performing several types of queries and updates on general rooted trees, binary search trees and lists of size N. For rooted trees we introduce…

Data Structures and Algorithms · Computer Science 2013-03-25 Mugurel Ionut Andreica