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Related papers: Contrastive Moments: Unsupervised Halfspace Learni…

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We study the efficient PAC learnability of halfspaces in the presence of Tsybakov noise. In the Tsybakov noise model, each label is independently flipped with some probability which is controlled by an adversary. This noise model…

Machine Learning · Computer Science 2020-06-12 Ilias Diakonikolas , Vasilis Kontonis , Christos Tzamos , Nikos Zarifis

Contrastive learning is a family of self-supervised methods where a model is trained to solve a classification task constructed from unlabeled data. It has recently emerged as one of the leading learning paradigms in the absence of labels…

Machine Learning · Statistics 2021-03-05 Bingbin Liu , Pradeep Ravikumar , Andrej Risteski

We use the Sum of Squares method to develop new efficient algorithms for learning well-separated mixtures of Gaussians and robust mean estimation, both in high dimensions, that substantially improve upon the statistical guarantees achieved…

Data Structures and Algorithms · Computer Science 2017-11-21 Samuel B. Hopkins , Jerry Li

A remarkable recent paper by Rubinfeld and Vasilyan (2022) initiated the study of \emph{testable learning}, where the goal is to replace hard-to-verify distributional assumptions (such as Gaussianity) with efficiently testable ones and to…

Machine Learning · Computer Science 2022-11-28 Aravind Gollakota , Adam R. Klivans , Pravesh K. Kothari

We provide efficient replicable algorithms for the problem of learning large-margin halfspaces. Our results improve upon the algorithms provided by Impagliazzo, Lei, Pitassi, and Sorrell [STOC, 2022]. We design the first…

Machine Learning · Computer Science 2025-10-15 Alkis Kalavasis , Amin Karbasi , Kasper Green Larsen , Grigoris Velegkas , Felix Zhou

We study the {\em robust proper learning} of univariate log-concave distributions (over continuous and discrete domains). Given a set of samples drawn from an unknown target distribution, we want to compute a log-concave hypothesis…

Data Structures and Algorithms · Computer Science 2016-06-10 Ilias Diakonikolas , Daniel M. Kane , Alistair Stewart

The low-degree polynomial framework has been highly successful in predicting computational versus statistical gaps for high-dimensional problems in average-case analysis and machine learning. This success has led to the low-degree…

Machine Learning · Statistics 2026-03-04 He Jia , Aravindan Vijayaraghavan

We present an improved algorithm for {\em quasi-properly} learning convex polyhedra in the realizable PAC setting from data with a margin. Our learning algorithm constructs a consistent polyhedron as an intersection of about $t \log t$…

Machine Learning · Computer Science 2021-11-03 Lee-Ad Gottlieb , Eran Kaufman , Aryeh Kontorovich , Gabriel Nivasch

We develop efficient algorithms for estimating low-degree moments of unknown distributions in the presence of adversarial outliers. The guarantees of our algorithms improve in many cases significantly over the best previous ones, obtained…

Data Structures and Algorithms · Computer Science 2017-12-27 Pravesh K. Kothari , David Steurer

We consider the problem of learning high dimensional polynomial transformations of Gaussians. Given samples of the form $p(x)$, where $x\sim N(0, \mathrm{Id}_r)$ is hidden and $p: \mathbb{R}^r \to \mathbb{R}^d$ is a function where every…

Machine Learning · Computer Science 2022-04-11 Sitan Chen , Jerry Li , Yuanzhi Li , Anru R. Zhang

In list-decodable subspace recovery, the input is a collection of $n$ points $\alpha n$ (for some $\alpha \ll 1/2$) of which are drawn i.i.d. from a distribution $\mathcal{D}$ with a isotropic rank $r$ covariance $\Pi_*$ (the…

Data Structures and Algorithms · Computer Science 2021-01-08 Ainesh Bakshi , Pravesh K. Kothari

We show hardness of improperly learning halfspaces in the agnostic model, both in the distribution-independent as well as the distribution-specific setting, based on the assumption that worst-case lattice problems, such as GapSVP or SIVP,…

Machine Learning · Computer Science 2023-02-21 Stefan Tiegel

Long-tailed distributions frequently emerge in real-world data, where a large number of minority categories contain a limited number of samples. Such imbalance issue considerably impairs the performance of standard supervised learning…

Machine Learning · Computer Science 2024-03-15 Chaoqun Du , Yulin Wang , Shiji Song , Gao Huang

We study the fundamental problem of high-dimensional mean estimation in a robust model where a constant fraction of the samples are adversarially corrupted. Recent work gave the first polynomial time algorithms for this problem with…

Machine Learning · Computer Science 2018-11-26 Yu Cheng , Ilias Diakonikolas , Rong Ge

We develop an extension of recently developed methods for obtaining time-space tradeoff lower bounds for problems of learning from random test samples to handle the situation where the space of tests is signficantly smaller than the space…

Machine Learning · Computer Science 2017-08-10 Paul Beame , Shayan Oveis Gharan , Xin Yang

Let $G$ be a bounded open subset of Euclidean space with real algebraic boundary $\Gamma$. Under the assumption that the degree $d$ of $\Gamma$ is given, and the power moments of the Lebesgue measure on $G$ are known up to order $3d$, we…

Optimization and Control · Mathematics 2014-02-07 Jean-Bernard Lasserre , Mihai Putinar

We study the fundamental problem of learning the parameters of a high-dimensional Gaussian in the presence of noise -- where an $\varepsilon$-fraction of our samples were chosen by an adversary. We give robust estimators that achieve…

Data Structures and Algorithms · Computer Science 2017-11-07 Ilias Diakonikolas , Gautam Kamath , Daniel M. Kane , Jerry Li , Ankur Moitra , Alistair Stewart

We give the first polynomial time and sample $(\epsilon, \delta)$-differentially private (DP) algorithm to estimate the mean, covariance and higher moments in the presence of a constant fraction of adversarial outliers. Our algorithm…

Machine Learning · Statistics 2021-12-08 Pravesh K. Kothari , Pasin Manurangsi , Ameya Velingker

We present a fairly general framework for reducing $(\varepsilon, \delta)$ differentially private (DP) statistical estimation to its non-private counterpart. As the main application of this framework, we give a polynomial time and…

Machine Learning · Statistics 2022-06-23 Hassan Ashtiani , Christopher Liaw

Fractional statistical moments are utilized for various tasks of uncertainty quantification, including the estimation of probability distributions. However, an estimation of fractional statistical moments of costly mathematical models by…

Methodology · Statistics 2024-03-05 Lukáš Novák , Marcos Valdebenito , Matthias Faes