English
Related papers

Related papers: Efficient Covariance Estimation for Sparsified Fun…

200 papers

Motivated by modern observational studies, we introduce a class of functional models that expands nested and crossed designs. These models account for the natural inheritance of correlation structure from sampling design in studies where…

Applications · Statistics 2013-04-26 Haochang Shou , Vadim Zipunnikov , Ciprian M. Crainiceanu , Sonja Greven

We study the problem of communication-efficient distributed vector mean estimation, a commonly used subroutine in distributed optimization and Federated Learning (FL). Rand-$k$ sparsification is a commonly used technique to reduce…

Distributed, Parallel, and Cluster Computing · Computer Science 2023-10-31 Shuli Jiang , Pranay Sharma , Gauri Joshi

We study the parameter estimation problem for a varying index coefficient model in high dimensions. Unlike the most existing works that iteratively estimate the parameters and link functions, based on the generalized Stein's identity, we…

Machine Learning · Statistics 2019-10-29 Sen Na , Zhuoran Yang , Zhaoran Wang , Mladen Kolar

We develop a method for estimating well-conditioned and sparse covariance and inverse covariance matrices from a sample of vectors drawn from a sub-gaussian distribution in high dimensional setting. The proposed estimators are obtained by…

Statistics Theory · Mathematics 2016-11-21 Ashwini Maurya

Estimating covariance parameters for multivariate spatial Gaussian random fields is computationally challenging, as the number of parameters grows rapidly with the number of variables, and likelihood evaluation requires operations of order…

Methodology · Statistics 2026-04-10 Francisco Cuevas-Pacheco , Gabriel Riffo , Xavier Emery

Correlated random fields are a common way to model dependence struc- tures in high-dimensional data, especially for data collected in imaging. One important parameter characterizing the degree of dependence is the asymp- totic variance…

Statistics Theory · Mathematics 2018-03-20 Annabel Prause , Ansgar Steland

Many causal estimands are only partially identifiable since they depend on the unobservable joint distribution between potential outcomes. Stratification on pretreatment covariates can yield sharper bounds; however, unless the covariates…

Econometrics · Economics 2024-11-19 Wenlong Ji , Lihua Lei , Asher Spector

Two algorithms are proposed to simulate space-time Gaussian random fields with a covariance function belonging to an extended Gneiting class, the definition of which depends on a completely monotone function associated with the spatial…

Computation · Statistics 2019-12-05 Denis Allard , Xavier Emery , Céline Lacaux , Christian Lantuéjoul

Gaussian process is a theoretically appealing model for nonparametric analysis, but its computational cumbersomeness hinders its use in large scale and the existing reduced-rank solutions are usually heuristic. In this work, we propose a…

Machine Learning · Statistics 2015-11-25 Leo L. Duan , Xia Wang , Rhonda D. Szczesniak

In this paper, we focus on the variable selection techniques for a class of semiparametric spatial regression models which allow one to study the effects of explanatory variables in the presence of the spatial information. The spatial…

Methodology · Statistics 2021-06-03 Guannan Wang , Jue Wang

The aim of this article is to propose a novel kernel estimator of the baseline function in a general high-dimensional Cox model, for which we derive non-asymptotic rates of convergence. To construct our estimator, we first estimate the…

Applications · Statistics 2015-07-07 Agathe Guilloux , Sarah Lemler , Marie-Luce Taupin

This paper focuses on variable selection for a partially linear single-index varying-coefficient model. A regularized variable selection procedure by combining basis function approximations with SCAD penalty is proposed. It can…

Statistics Theory · Mathematics 2024-12-19 Lijuan Han , Liugen Xue , Junshan Xie

Sparse variational approximations are popular methods for scaling up inference and learning in Gaussian processes to larger datasets. For $N$ training points, exact inference has $O(N^3)$ cost; with $M \ll N$ features, state of the art…

Machine Learning · Statistics 2024-04-15 Talay M Cheema , Carl Edward Rasmussen

We present configuration-space estimators for the auto- and cross-covariance of two- and three-point correlation functions (2PCF and 3PCF) in general survey geometries. These are derived in the Gaussian limit (setting higher-order…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Oliver H. E. Philcox , Daniel J. Eisenstein

In this paper, a shrinkage estimator for the population mean is proposed under known quadratic loss functions with unknown covariance matrices. The new estimator is non-parametric in the sense that it does not assume a specific parametric…

Methodology · Statistics 2014-11-07 Cheng Wang , Tiejun Tong , Longbing Cao , Baiqi Miao

In distributed, or privacy-preserving learning, we are often given a set of probabilistic models estimated from different local repositories, and asked to combine them into a single model that gives efficient statistical estimation. A…

Machine Learning · Statistics 2017-03-01 Jun Han , Qiang Liu

Spatio-temporal covariances are important for describing the spatio-temporal variability of underlying random processes in geostatistical data. For second-order stationary processes, there exist subclasses of covariance functions that…

Applications · Statistics 2017-05-05 Huang Huang , Ying Sun

There are many interesting and widely used estimators of a functional with finite semiparametric variance bound that depend on nonparametric estimators of nuisance functions. We use cross-fitting (i.e. sample splitting) to construct novel…

Statistics Theory · Mathematics 2018-01-30 Whitney K. Newey , James R. Robins

Incorporating covariates into functional principal component analysis (PCA) can substantially improve the representation efficiency of the principal components and predictive performance. However, many existing functional PCA methods do not…

Methodology · Statistics 2023-08-22 Fei Ding , Shiyuan He , David E. Jones , Jianhua Z. Huang

The assumption of separability is a simplifying and very popular assumption in the analysis of spatio-temporal or hypersurface data structures. It is often made in situations where the covariance structure cannot be easily estimated, for…

Methodology · Statistics 2019-01-03 Pramita Bagchi , Holger Dette