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Gaussian Processes (GP) have become popular machine-learning methods for kernel-based learning on datasets with complicated covariance structures. In this paper, we present a novel extension to the GP framework using a contaminated normal…

Machine Learning · Computer Science 2024-07-03 Daniel Iong , Matthew McAnear , Yuezhou Qu , Shasha Zou , Gabor Toth , Yang Chen

A spline chaos expansion, referred to as SCE, is introduced for uncertainty quantification analysis. The expansion provides a means for representing an output random variable of interest with respect to multivariate orthonormal basis…

Numerical Analysis · Mathematics 2019-11-12 Sharif Rahman

We present a unified framework for estimation and analysis of generalized additive models in high dimensions. The framework defines a large class of penalized regression estimators, encompassing many existing methods. An efficient…

Methodology · Statistics 2019-03-13 Asad Haris , Noah Simon , Ali Shojaie

This paper introduces an efficient sparse recovery approach for Polynomial Chaos (PC) expansions, which promotes the sparsity by breaking the dimensionality of the problem. The proposed algorithm incrementally explores sub-dimensional…

Computation · Statistics 2017-04-05 Negin Alemazkoor , Hadi Meidani

We show convergence rates for a sparse grid approximation of the distribution of solutions of the stochastic Landau-Lifshitz-Gilbert equation. Beyond being a frequently studied equation in engineering and physics, the stochastic…

Numerical Analysis · Mathematics 2025-06-02 Xin An , Josef Dick , Michael Feischl , Andrea Scaglioni , Thanh Tran

This paper suggests a nonparametric scheme to find the sparse solution of the underdetermined system of linear equations in the presence of unknown impulsive or non-Gaussian noise. This approach is robust against any variations of the noise…

Computer Vision and Pattern Recognition · Computer Science 2012-01-16 Mahmoud Ramezani Mayiami , Babak Seyfe

Consider a linear model $Y=X\beta+z$, where $X=X_{n,p}$ and $z\sim N(0,I_n)$. The vector $\beta$ is unknown but is sparse in the sense that most of its coordinates are $0$. The main interest is to separate its nonzero coordinates from the…

Statistics Theory · Mathematics 2015-03-20 Zheng Tracy Ke , Jiashun Jin , Jianqing Fan

Regularization of ill-posed linear inverse problems via $\ell_1$ penalization has been proposed for cases where the solution is known to be (almost) sparse. One way to obtain the minimizer of such an $\ell_1$ penalized functional is via an…

Numerical Analysis · Mathematics 2013-01-01 I. Daubechies , M. Fornasier , I. Loris

We present the framework of slowly varying regression under sparsity, allowing sparse regression models to exhibit slow and sparse variations. The problem of parameter estimation is formulated as a mixed-integer optimization problem. We…

Machine Learning · Computer Science 2023-11-14 Dimitris Bertsimas , Vassilis Digalakis , Michael Linghzi Li , Omar Skali Lami

We propose a sparse grid stochastic collocation method for long-time simulations of stochastic differential equations (SDEs) driven by white noise. The method uses pre-determined sparse quadrature rules for the forcing term and constructs…

Numerical Analysis · Mathematics 2017-06-13 H. Cagan Ozen , Guillaume Bal

Probabilistic evaluation improves the trade-off between target coverage and OAR sparing in IMPT but remains computationally demanding. This study proposes sparse probabilistic evaluation (SPE), a computationally efficient approach…

We consider the sparse optimization problem with nonlinear constraints and an objective function, which is given by the sum of a general smooth mapping and an additional term defined by the $ \ell_0 $-quasi-norm. This term is used to obtain…

Optimization and Control · Mathematics 2022-10-19 Christian Kanzow , Alexandra Schwarz , Felix Weiß

The sparse generalized eigenvalue problem arises in a number of standard and modern statistical learning models, including sparse principal component analysis, sparse Fisher discriminant analysis, and sparse canonical correlation analysis.…

Numerical Analysis · Computer Science 2019-03-05 Ganzhao Yuan , Li Shen , Wei-Shi Zheng

This paper proposes a sparse regression strategy for discovery of ordinary differential equations from incomplete and noisy data. Inference is performed over both equation parameters and state variables using a statistically motivated…

Dynamical Systems · Mathematics 2026-02-18 Teddy Meissner , Karl Glasner

Sparse covariates are frequent in classification and regression problems and in these settings the task of variable selection is usually of interest. As it is well known, sparse statistical models correspond to situations where there are…

Methodology · Statistics 2020-02-14 Ana M. Bianco , Graciela Boente , Gonzalo Chebi

Sparse linear (or generalized linear) models combine a standard likelihood function with a sparse prior on the unknown coefficients. These priors can conveniently be expressed as a maximization over zero-mean Gaussians with different…

Machine Learning · Statistics 2012-07-11 David Wipf , Yi Wu

Sparse regression and variable selection for large-scale data have been rapidly developed in the past decades. This work focuses on sparse ridge regression, which enforces the sparsity by use of the L0 norm. We first prove that the…

Computation · Statistics 2020-06-30 Weijun Xie , Xinwei Deng

Sufficient dimension reduction (SDR) in regression, which reduces the dimension by replacing original predictors with a minimal set of their linear combinations without loss of information, is very helpful when the number of predictors is…

Statistics Theory · Mathematics 2012-11-15 Xin Chen , Changliang Zou , R. Dennis Cook

Renormalized homotopy continuation on toric varieties is introduced as a tool for solving sparse systems of polynomial equations, or sparse systems of exponential sums. The cost of continuation depends on a renormalized condition length,…

Numerical Analysis · Mathematics 2025-06-23 Gregorio Malajovich

We address numerical differentiation under coarse, non-uniform sampling and Gaussian noise. A maximum-likelihood estimator with $L_2$-norm constraint on a higher-order derivative is obtained, yielding spline-based solution. We introduce a…

Methodology · Statistics 2025-07-31 Konstantin E. Avrachenkov , Leonid B. Freidovich