English
Related papers

Related papers: Faster Approximate Fixed Points of $\ell_\infty$-C…

200 papers

We study the problem of finding an $\epsilon$-fixed point of a contraction map $f:[0,1]^k\mapsto[0,1]^k$ under both the $\ell_\infty$-norm and the $\ell_1$-norm. For both norms, we give an algorithm with running time $O(\log^{\lceil…

Computational Complexity · Computer Science 2026-02-12 Xi Chen , Yuhao Li , Mihalis Yannakakis

We prove that an $\epsilon$-approximate fixpoint of a map $f:[0,1]^d\rightarrow [0,1]^d$ can be found with $\mathcal{O}(d^2(\log\frac{1}{\epsilon} + \log\frac{1}{1-\lambda}))$ queries to $f$ if $f$ is $\lambda$-contracting with respect to…

Computational Complexity · Computer Science 2025-03-31 Sebastian Haslebacher , Jonas Lill , Patrick Schnider , Simon Weber

We study functions $f : [0, 1]^d \rightarrow [0, 1]^d$ that are both monotone and contracting, and we consider the problem of finding an $\varepsilon$-approximate fixed point of $f$. We show that the problem lies in the complexity class…

Computational Complexity · Computer Science 2025-03-28 Eleni Batziou , John Fearnley , Spencer Gordon , Ruta Mehta , Rahul Savani

We give an algorithm for finding an $\epsilon$-fixed point of a contraction map $f:[0,1]^k\mapsto[0,1]^k$ under the $\ell_\infty$-norm with query complexity $O (k\log (1/\epsilon ) )$.

Computational Complexity · Computer Science 2025-08-12 Xi Chen , Yuhao Li , Mihalis Yannakakis

We propose a new algorithm that finds an $\varepsilon$-approximate fixed point of a smooth function from the $n$-dimensional $\ell_2$ unit ball to itself. We use the general framework of finding approximate solutions to a variational…

Computer Science and Game Theory · Computer Science 2025-01-22 Idan Attias , Yuval Dagan , Constantinos Daskalakis , Rui Yao , Manolis Zampetakis

We provide faster algorithms for approximately solving $\ell_{\infty}$ regression, a fundamental problem prevalent in both combinatorial and continuous optimization. In particular, we provide accelerated coordinate descent methods capable…

Data Structures and Algorithms · Computer Science 2020-04-03 Aaron Sidford , Kevin Tian

We study the query complexity of finding a Tarski fixed point over the $k$-dimensional grid $\{1,\ldots,n\}^k$. Improving on the previous best upper bound of $\smash{O(\log^{\lceil 2k/3\rceil} n)}$ [FPS20], we give a new algorithm with…

Computer Science and Game Theory · Computer Science 2022-05-24 Xi Chen , Yuhao Li

Building on existing $hp$-adaptive algorithms driven by equilibrated-flux estimators from [ESAIM Math. Model. Numer. Anal. 57 (2023), 329--366] and the references therein, we propose a novel $h$-adaptive algorithm for a fixed polynomial…

Numerical Analysis · Mathematics 2026-03-11 Théophile Chaumont-Frelet , Zhaonan Dong , Gregor Gantner , Martin Vohralík

We propose a fast proximal Newton-type algorithm for minimizing regularized finite sums that returns an $\epsilon$-suboptimal point in $\tilde{\mathcal{O}}(d(n + \sqrt{\kappa d})\log(\frac{1}{\epsilon}))$ FLOPS, where $n$ is number of…

Machine Learning · Computer Science 2017-08-30 Xuanqing Liu , Cho-Jui Hsieh , Jason D. Lee , Yuekai Sun

We give a reduction from $(1+\varepsilon)$-approximate Earth Mover's Distance (EMD) to $(1+\varepsilon)$-approximate Closest Pair (CP). As a consequence, we improve the fastest known approximation algorithm for high-dimensional EMD. Here,…

Data Structures and Algorithms · Computer Science 2025-08-27 Lorenzo Beretta , Vincent Cohen-Addad , Rajesh Jayaram , Erik Waingarten

We generalize the monotone local search approach of Fomin, Gaspers, Lokshtanov and Saurabh [J. ACM 2019], by establishing a connection between parameterized approximation and exponential-time approximation algorithms for monotone subset…

Data Structures and Algorithms · Computer Science 2026-01-13 Barış Can Esmer , Ariel Kulik , Dániel Marx , Daniel Neuen , Roohani Sharma

We propose a new $(1+O(\varepsilon))$-approximation algorithm with $O(n+ 1/\varepsilon^{\frac{(d-1)}{2}})$ running time for computing the diameter of a set of $n$ points in the $d$-dimensional Euclidean space for a fixed dimension $d$,…

Computational Geometry · Computer Science 2020-11-11 Mahdi Imanparast , Seyed Naser Hashemi

Given a text $T$ of length $n$ and a pattern $P$ of length $m$, the approximate pattern matching problem asks for computation of a particular \emph{distance} function between $P$ and every $m$-substring of $T$. We consider a…

Data Structures and Algorithms · Computer Science 2019-07-24 Jan Studený , Przemysław Uznański

We give an $O(\log^2 n)$-query algorithm for finding a Tarski fixed point over the $4$-dimensional lattice $[n]^4$, matching the $\Omega(\log^2 n)$ lower bound of [EPRY20]. Additionally, our algorithm yields an ${O(\log^{\lceil…

Computational Complexity · Computer Science 2026-04-02 Xi Chen , Yuhao Li , Mihalis Yannakakis

Finding approximate stationary points, i.e., points where the gradient is approximately zero, of non-convex but smooth objective functions $f$ over unrestricted $d$-dimensional domains is one of the most fundamental problems in classical…

Optimization and Control · Mathematics 2024-09-13 Alexandros Hollender , Manolis Zampetakis

The design of fixed point algorithms is at the heart of monotone operator theory, convex analysis, and of many modern optimization problems arising in machine learning and control. This tutorial reviews recent advances in understanding the…

Optimization and Control · Mathematics 2022-07-19 Francesco Bullo , Pedro Cisneros-Velarde , Alexander Davydov , Saber Jafarpour

We study density thresholds that force a measurable set $E\subseteq\mathbb{R}^d$ to contain all sufficiently large similar copies of every $n$-point configuration. We prove a lower bound of the form $1-O((\log n)/n)$, which matches the…

Classical Analysis and ODEs · Mathematics 2026-04-21 Vjekoslav Kovač , Adian Anibal Santos Sepčić

Recent works in dimensionality reduction for regression tasks have introduced the notion of sensitivity, an estimate of the importance of a specific datapoint in a dataset, offering provable guarantees on the quality of the approximation…

Machine Learning · Computer Science 2023-11-22 Swati Padmanabhan , David P. Woodruff , Qiuyi Zhang

This paper primarily focuses on computing the Euclidean projection of a vector onto the $\ell_{p}$ ball in which $p\in(0,1)$. Such a problem emerges as the core building block in statistical machine learning and signal processing tasks…

Optimization and Control · Mathematics 2024-10-28 Xiangyu Yang , Jiashan Wang , Hao Wang

We resolve a long-standing open question, about the existence of a constant-factor approximation algorithm for the average-case \textsc{Decision Tree} problem with uniform probability distribution over the hypotheses. We answer the question…

Data Structures and Algorithms · Computer Science 2026-04-29 Michał Szyfelbein
‹ Prev 1 2 3 10 Next ›