English
Related papers

Related papers: Being even slightly shallow makes life hard

200 papers

We give a 2-approximation algorithm for Non-Uniform Sparsest Cut that runs in time $n^{O(k)}$, where $k$ is the treewidth of the graph. This improves on the previous $2^{2^k}$-approximation in time $\poly(n) 2^{O(k)}$ due to Chlamt\'a\v{c}…

Data Structures and Algorithms · Computer Science 2013-05-08 Anupam Gupta , Kunal Talwar , David Witmer

Dense subgraph discovery aims to find a dense component in edge-weighted graphs. This is a fundamental graph-mining task with a variety of applications and thus has received much attention recently. Although most existing methods assume…

Machine Learning · Computer Science 2020-06-25 Yuko Kuroki , Atsushi Miyauchi , Junya Honda , Masashi Sugiyama

Tight and efficient neural network bounding is crucial to the scaling of neural network verification systems. Many efficient bounding algorithms have been presented recently, but they are often too loose to verify more challenging…

Machine Learning · Computer Science 2024-02-27 Alessandro De Palma , Harkirat Singh Behl , Rudy Bunel , Philip H. S. Torr , M. Pawan Kumar

Several probabilistic models from high-dimensional statistics and machine learning reveal an intriguing --and yet poorly understood-- dichotomy. Either simple local algorithms succeed in estimating the object of interest, or even…

Discrete Mathematics · Computer Science 2016-10-19 Zhou Fan , Andrea Montanari

De Berg et al. in [SICOMP 2020] gave an algorithmic framework for subexponential algorithms on geometric graphs with tight (up to ETH) running times. This framework is based on dynamic programming on graphs of weighted treewidth resulting…

Data Structures and Algorithms · Computer Science 2021-07-15 Fedor V. Fomin , Petr A. Golovach , Tanmay Inamdar , Saket Saurabh

The problem of computing minimally sparse solutions of under-determined linear systems is $NP$ hard in general. Subsets with extra properties, may allow efficient algorithms, most notably problems with the restricted isometry property (RIP)…

Machine Learning · Computer Science 2023-02-07 G. Welper

Given a simplicial complex with $n$ simplices, we consider the Connected Subsurface Recognition (c-SR) problem of finding a subcomplex that is homeomorphic to a given connected surface with a fixed boundary. We also study the related…

Computational Geometry · Computer Science 2022-03-16 Mitchell Black , Nello Blaser , Amir Nayyeri , Erlend Raa Vågset

For random graphs, the containment problem considers the probability that a binomial random graph $G(n,p)$ contains a given graph as a substructure. When asking for the graph as a topological minor, i.e., for a copy of a subdivision of the…

Combinatorics · Mathematics 2015-05-05 Anna Gundert , Uli Wagner

We give an algorithmic and lower-bound framework that facilitates the construction of subexponential algorithms and matching conditional complexity bounds. It can be applied to intersection graphs of similarly-sized fat objects, yielding…

Computational Geometry · Computer Science 2020-12-18 Mark de Berg , Hans L. Bodlaender , Sándor Kisfaludi-Bak , Dániel Marx , Tom C. van der Zanden

Identifying the nodes of small sub-graphs with no a priori information is a hard problem. In this work, we want to find each node of a sparse sub-graph embedded in both dynamic and static background graphs, of larger average degree. We show…

Data Structures and Algorithms · Computer Science 2015-06-22 Vincenzo Fioriti , Marta Chinnici

Subgraph Isomorphism is a very basic graph problem, where given two graphs $G$ and $H$ one is to check whether $G$ is a subgraph of $H$. Despite its simple definition, the Subgraph Isomorphism problem turns out to be very broad, as it…

Data Structures and Algorithms · Computer Science 2015-04-14 Marek Cygan , Jakub Pachocki , Arkadiusz Socała

A dynamic graph algorithm is a data structure that answers queries about a property of the current graph while supporting graph modifications such as edge insertions and deletions. Prior work has shown strong conditional lower bounds for…

Data Structures and Algorithms · Computer Science 2023-01-30 Monika Henzinger , Ami Paz , A. R. Sricharan

The Subgraph Isomorphism problem is of considerable importance in computer science. We examine the problem when the pattern graph H is of bounded treewidth, as occurs in a variety of applications. This problem has a well-known algorithm via…

Data Structures and Algorithms · Computer Science 2021-05-12 Karl Bringmann , Jasper Slusallek

Many algorithms have been developed for NP-hard problems on graphs with small treewidth $k$. For example, all problems that are expressable in linear extended monadic second order can be solved in linear time on graphs of bounded treewidth.…

Data Structures and Algorithms · Computer Science 2016-05-17 Frank Kammer , Torsten Tholey

A function on a topological space is called unimodal if all of its super-level sets are contractible. A minimal unimodal decomposition of a function $f$ is the smallest number of unimodal functions that sum up to $f$. The problem of…

Algebraic Topology · Mathematics 2025-10-08 Mishal Assif P K , Yuliy Baryshnikov

Finding dense subgraphs of a large graph is a standard problem in graph mining that has been studied extensively both for its theoretical richness and its many practical applications. In this paper we introduce a new family of dense…

Data Structures and Algorithms · Computer Science 2021-06-07 Nate Veldt , Austin R. Benson , Jon Kleinberg

We investigate the difficulties of training sparse neural networks and make new observations about optimization dynamics and the energy landscape within the sparse regime. Recent work of \citep{Gale2019, Liu2018} has shown that sparse…

Machine Learning · Computer Science 2020-10-08 Utku Evci , Fabian Pedregosa , Aidan Gomez , Erich Elsen

We prove several tight results on the fine-grained complexity of approximating the diameter of a graph. First, we prove that, for any $\varepsilon>0$, assuming the Strong Exponential Time Hypothesis (SETH), there are no near-linear time…

Data Structures and Algorithms · Computer Science 2021-04-05 Ray Li

A central problem in graph mining is finding dense subgraphs, with several applications in different fields, a notable example being identifying communities. While a lot of effort has been put on the problem of finding a single dense…

Data Structures and Algorithms · Computer Science 2019-01-31 Riccardo Dondi , Mohammad Mehdi Hosseinzadeh , Giancarlo Mauri , Italo Zoppis

We design an algorithm for computing connectivity in hypergraphs which runs in time $\hat O_r(p + \min\{\lambda^{\frac{r-3}{r-1}} n^2, n^r/\lambda^{r/(r-1)}\})$ (the $\hat O_r(\cdot)$ hides the terms subpolynomial in the main parameter and…

Data Structures and Algorithms · Computer Science 2021-11-16 Calvin Beideman , Karthekeyan Chandrasekaran , Sagnik Mukhopadhyay , Danupon Nanongkai