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Let us say that an element of a given family $\A$ of subsets of $\R^d$ can be reconstructed using $n$ test sets if there exist $T_1,...,T_n \subset \R^d$ such that whenever $A,B\in \A$ and the Lebesgue measures of $A \cap T_i$ and $B \cap…

Classical Analysis and ODEs · Mathematics 2014-09-23 Márton Elekes , Tamás Keleti , András Máthé

Let K be a convex body in $R^d$. A random polytope is the convex hull $[x_1,...,x_n]$ of finitely many points chosen at random in K. $\Bbb E(K,n)$ is the expectation of the volume of a random polytope of n randomly chosen points. I.…

Metric Geometry · Mathematics 2016-09-06 Carsten Schütt

We introduce the flag-approximability of a convex body to measure how easy it is to approximate by polytopes. We show that the flag-approximability is exactly half the volume entropy of the Hilbert geometry on the body, and that both…

Metric Geometry · Mathematics 2018-09-26 Constantin Vernicos , Cormac Walsh

In this paper, we consider the problem of replicable realizable PAC learning. We construct a particularly hard learning problem and show a sample complexity lower bound with a close to $(\log|H|)^{3/2}$ dependence on the size of the…

Machine Learning · Computer Science 2026-02-24 Kasper Green Larsen , Markus Engelund Mathiasen , Chirag Pabbaraju , Clement Svendsen

The aim of this paper is to present some properties of reduced spherical convex bodies on the two-dimensional sphere $S^2$. The intersection of two different non-opposite hemispheres is called a lune. By its thickness we mean the distance…

Metric Geometry · Mathematics 2016-07-04 Marek Lassak , Michał Musielak

We prove that for any compact set B in R^d and for any epsilon >0 there is a finite subset X of B of |X|=d^{O(1/epsilon^2)} points such that the maximum absolute value of any linear function ell: R^d --> R on X approximates the maximum…

Metric Geometry · Mathematics 2012-04-13 Alexander Barvinok

Hadwiger's conjecture in convex geometry, formulated in 1957, states that every convex body in $\mathbb{R}^n$ can be covered by $2^n$ translations of its interior. Despite significant efforts, the best known bound related to this problem…

Metric Geometry · Mathematics 2024-10-16 Daniel Galicer , Joaquín Singer

We consider the discrepancy of the integer lattice with respect to the collection of all translated copies of a dilated convex body having a finite number of flat, possibly non-smooth, points in its boundary. We estimate the $L^{p}$ norm of…

Functional Analysis · Mathematics 2018-10-02 Luca Brandolini , Leonardo Colzani , Bianca Gariboldi , Giacomo Gigante , Giancarlo Travaglini

We introduce a family of symmetric convex bodies called generalized ellipsoids of degree $d$ (GE-$d$s), with ellipsoids corresponding to the case of $d=0$. Generalized ellipsoids (GEs) retain many geometric, algebraic, and algorithmic…

Optimization and Control · Mathematics 2025-07-01 Amir Ali Ahmadi , Abraar Chaudhry , Cemil Dibek

We study the sample complexity of stochastic convex optimization when problem parameters, e.g., the distance to optimality, are unknown. We pursue two strategies. First, we develop a reliable model selection method that avoids overfitting…

Machine Learning · Computer Science 2025-06-16 Jared Lawrence , Ari Kalinsky , Hannah Bradfield , Yair Carmon , Oliver Hinder

Let a random simplex in a d-dimensional convex body be the convex hull of d+1 random points from the body. We study the following question: As a function of the convex body, is the expected volume of a random simplex monotone non-decreasing…

Probability · Mathematics 2014-01-14 Luis Rademacher

We give a variety of uniqueness results for minimal ellipsoids circumscribing and maximal ellipsoids inscribed into a convex body. Uniqueness follows from a convexity or concavity criterion on the function used to measure the size of the…

Metric Geometry · Mathematics 2012-05-10 Matthias J. Weber , Hans-Peter Schröcker

We introduce a notion of $k$-convexity and explore polygons in the plane that have this property. Polygons which are \mbox{$k$-convex} can be triangulated with fast yet simple algorithms. However, recognizing them in general is a 3SUM-hard…

Computational Geometry · Computer Science 2010-07-22 Oswin Aichholzer , Franz Aurenhammer , Erik D. Demaine , Ferran Hurtado , Pedro Ramos , Jorge Urrutia

Let $K\subset\mathbb S^{d-1}$ be a convex spherical body. Denote by $\Delta(K)$ the distance between two random points in $K$ and denote by $\sigma(K)$ the length of a random chord of $K$. We explicitly express the distribution of…

Probability · Mathematics 2020-07-16 Tatiana Moseeva , Alexander Tarasov , Dmitry Zaporozhets

The basic problem in the PAC model of computational learning theory is to determine which hypothesis classes are efficiently learnable. There is presently a dearth of results showing hardness of learning problems. Moreover, the existing…

Machine Learning · Computer Science 2014-03-11 Amit Daniely , Nati Linial , Shai Shalev-Shwartz

We study the problem of learning a hypergraph via edge detecting queries. In this problem, a learner queries subsets of vertices of a hidden hypergraph and observes whether these subsets contain an edge or not. In general, learning a…

Data Structures and Algorithms · Computer Science 2024-12-23 Eric Balkanski , Oussama Hanguir , Shatian Wang

Model generalization of the underlying dynamics is critical for achieving data efficiency when learning for robot control. This paper proposes a novel approach for learning dynamics leveraging the symmetry in the underlying robotic system,…

Robotics · Computer Science 2022-10-17 Jee-eun Lee , Jaemin Lee , Tirthankar Bandyopadhyay , Luis Sentis

We study the problem of binary classification from the point of view of learning convex polyhedra in Hilbert spaces, to which one can reduce any binary classification problem. The problem of learning convex polyhedra in finite-dimensional…

Machine Learning · Computer Science 2023-03-06 Sergei Chubanov

In connection with an unsolved problem of Bang (1951) we give a lower bound for the sum of the base volumes of cylinders covering a d-dimensional convex body in terms of the relevant basic measures of the given convex body. As an…

Metric Geometry · Mathematics 2011-09-29 Karoly Bezdek , Alexander Litvak

We prove that for every convex body $K$ with the center of mass at the origin and every $\varepsilon\in \left(0,\frac{1}{2}\right)$, there exists a convex polytope $P$ with at most $e^{O(d)}\varepsilon^{-\frac{d-1}{2}}$ vertices such that…

Classical Analysis and ODEs · Mathematics 2017-05-05 Márton Naszódi , Fedor Nazarov , Dmitry Ryabogin