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Related papers: Learning Multivariate Log-concave Distributions

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We consider a reinforcement learning setting in which the deployment environment is different from the training environment. Applying a robust Markov decision processes formulation, we extend the distributionally robust $Q$-learning…

Machine Learning · Computer Science 2024-08-02 Shengbo Wang , Nian Si , Jose Blanchet , Zhengyuan Zhou

For the task of sampling from a density $\pi \propto \exp(-V)$ on $\mathbb{R}^d$, where $V$ is possibly non-convex but $L$-gradient Lipschitz, we prove that averaged Langevin Monte Carlo outputs a sample with $\varepsilon$-relative Fisher…

Statistics Theory · Mathematics 2022-02-11 Krishnakumar Balasubramanian , Sinho Chewi , Murat A. Erdogdu , Adil Salim , Matthew Zhang

For a $d$-dimensional log-concave distribution $\pi(\theta) \propto e^{-f(\theta)}$ constrained to a convex body $K$, the problem of outputting samples from a distribution $\nu$ which is $\varepsilon$-close in infinity-distance…

Data Structures and Algorithms · Computer Science 2022-11-14 Oren Mangoubi , Nisheeth K. Vishnoi

In this paper, we provide non-asymptotic upper bounds on the error of sampling from a target density using three schemes of discretized Langevin diffusions. The first scheme is the Langevin Monte Carlo (LMC) algorithm, the Euler…

Statistics Theory · Mathematics 2021-12-07 Arnak S. Dalalyan , Avetik Karagulyan , Lionel Riou-Durand

We study the complexity of sampling, rounding, and integrating arbitrary logconcave functions. Our new approach provides the first complexity improvements in nearly two decades for general logconcave functions for all three problems, and…

Data Structures and Algorithms · Computer Science 2024-11-21 Yunbum Kook , Santosh S. Vempala

We study the problem of sampling from a distribution $\mu$ with density $\propto e^{-V}$ for some potential function $V:\mathbb R^d\to \mathbb R$ with query access to $V$ and $\nabla V$. We start with the following standard assumptions: (1)…

Data Structures and Algorithms · Computer Science 2026-02-10 Yuchen He , Zhehan Lei , Jianan Shao , Chihao Zhang

Multi-distribution learning is a natural generalization of PAC learning to settings with multiple data distributions. There remains a significant gap between the known upper and lower bounds for PAC-learnable classes. In particular, though…

Machine Learning · Computer Science 2023-07-25 Pranjal Awasthi , Nika Haghtalab , Eric Zhao

The estimation of a log-concave density on $\mathbb{R}$ is a canonical problem in the area of shape-constrained nonparametric inference. We present a Bayesian nonparametric approach to this problem based on an exponentiated Dirichlet…

Statistics Theory · Mathematics 2020-07-14 Ester Mariucci , Kolyan Ray , Botond Szabo

Multi-distribution learning generalizes the classic PAC learning to handle data coming from multiple distributions. Given a set of $k$ data distributions and a hypothesis class of VC dimension $d$, the goal is to learn a hypothesis that…

Machine Learning · Computer Science 2024-01-30 Binghui Peng

We propose a sampling algorithm that achieves superior complexity bounds in all the classical settings (strongly log-concave, log-concave, Logarithmic-Sobolev inequality (LSI), Poincar\'e inequality) as well as more general settings with…

Statistics Theory · Mathematics 2023-06-29 Jiaojiao Fan , Bo Yuan , Yongxin Chen

We present an algorithm for the statistical learning setting with a bounded exp-concave loss in $d$ dimensions that obtains excess risk $O(d \log(1/\delta)/n)$ with probability at least $1 - \delta$. The core technique is to boost the…

Machine Learning · Computer Science 2016-10-17 Nishant A. Mehta

We consider the branch-length estimation problem on a bifurcating tree: a character evolves along the edges of a binary tree according to a two-state symmetric Markov process, and we seek to recover the edge transition probabilities from…

Computation · Statistics 2025-07-30 David Clancy , Hanbaek Lyu , Sebastien Roch

We study regression of $1$-Lipschitz functions under a log-concave measure $\mu$ on $\mathbb{R}^d$. We focus on the high-dimensional regime where the sample size $n$ is subexponential in $d$, in which distribution-free estimators are…

Probability · Mathematics 2025-09-15 Pierre Bizeul , Boaz Klartag

Let X_1, ..., X_n be independent and identically distributed random vectors with a log-concave (Lebesgue) density f. We first prove that, with probability one, there exists a unique maximum likelihood estimator of f. The use of this…

Methodology · Statistics 2008-04-25 Madeleine Cule , Richard Samworth , Michael Stewart

In this paper we consider learning in passive setting but with a slight modification. We assume that the target expected loss, also referred to as target risk, is provided in advance for learner as prior knowledge. Unlike most studies in…

Machine Learning · Computer Science 2013-05-21 Mehrdad Mahdavi , Rong Jin

The log-concave maximum likelihood estimator of a density on the real line based on a sample of size $n$ is known to attain the minimax optimal rate of convergence of $O(n^{-4/5})$ with respect to, e.g., squared Hellinger distance. In this…

Statistics Theory · Mathematics 2016-09-06 Arlene K. H. Kim , Adityanand Guntuboyina , Richard J. Samworth

Shape-constrained density estimation is an important topic in mathematical statistics. We focus on densities on $\mathbb{R}^d$ that are log-concave, and we study geometric properties of the maximum likelihood estimator (MLE) for weighted…

Methodology · Statistics 2022-07-25 Elina Robeva , Bernd Sturmfels , Caroline Uhler

Sampling from high-dimensional probability distributions is fundamental in machine learning and statistics. As datasets grow larger, computational efficiency becomes increasingly important, particularly in reducing adaptive complexity,…

Data Structures and Algorithms · Computer Science 2025-09-23 Huanjian Zhou , Masashi Sugiyama

Contrastive learning is a highly successful technique for learning representations of data from labeled tuples, specifying the distance relations within the tuple. We study the sample complexity of contrastive learning, i.e. the minimum…

Machine Learning · Computer Science 2023-12-04 Noga Alon , Dmitrii Avdiukhin , Dor Elboim , Orr Fischer , Grigory Yaroslavtsev

The overarching goal of this paper is to derive excess risk bounds for learning from exp-concave loss functions in passive and sequential learning settings. Exp-concave loss functions encompass several fundamental problems in machine…

Machine Learning · Computer Science 2014-02-11 Mehrdad Mahdavi , Rong Jin