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Existing methods for differentiable structure learning in discrete data typically assume that the data are generated from specific structural equation models. However, these assumptions may not align with the true data-generating process,…

Machine Learning · Computer Science 2025-10-28 Chang Deng , Bryon Aragam

We introduce a technique for estimating a structured covariance matrix from observations of a random vector which have been sketched. Each observed random vector $\boldsymbol{x}_t$ is reduced to a single number by taking its inner product…

Information Theory · Computer Science 2015-10-09 Sohail Bahmani , Justin Romberg

Community detection is an important problem when processing network data. Traditionally, this is done by exploiting the connections between nodes, but connections can be too sparse to detect communities in many real datasets. Node…

Methodology · Statistics 2023-06-29 Yaofang Hu , Wanjie Wang

Weakly supervised person search aims to jointly detect and match persons with only bounding box annotations. Existing approaches typically focus on improving the features by exploring relations of persons. However, scale variation problem…

Computer Vision and Pattern Recognition · Computer Science 2024-01-04 Benzhi Wang , Yang Yang , Jinlin Wu , Guo-jun Qi , Zhen Lei

In this paper, we consider voxel selection for functional Magnetic Resonance Imaging (fMRI) brain data with the aim of finding a more complete set of probably correlated discriminative voxels, thus improving interpretation of the discovered…

Computer Vision and Pattern Recognition · Computer Science 2015-06-09 Yilun Wang , Junjie Zheng , Sheng Zhang , Xujun Duan , Huafu Chen

Complex networks with directed, local interactions are ubiquitous in nature, and often occur with probabilistic connections due to both intrinsic stochasticity and disordered environments. Sparse non-Hermitian random matrices arise…

Disordered Systems and Neural Networks · Physics 2019-12-04 Grace H. Zhang , David R. Nelson

Sparse Bayesian learning (SBL) is a powerful framework for tackling the sparse coding problem. However, the most popular inference algorithms for SBL become too expensive for high-dimensional settings, due to the need to store and compute a…

Signal Processing · Electrical Eng. & Systems 2022-02-28 Alexander Lin , Andrew H. Song , Berkin Bilgic , Demba Ba

In neuroimaging, a large number of correlated tests are routinely performed to detect active voxels in single-subject experiments or to detect regions that differ between individuals belonging to different groups. In order to bound the…

We consider inference problems for high-dimensional (HD) functional data with a dense number (T) of repeated measurements taken for a large number of p variables from a small number of n experimental units. The spatial and temporal…

Methodology · Statistics 2020-05-06 Shawn Santo , Ping-Shou Zhong

Covariance matrices are fundamental to the analysis and forecast of economic, physical and biological systems. Although the eigenvalues $\{\lambda_i\}$ and eigenvectors $\{{\bf u}_i\}$ of a covariance matrix are central to such endeavors,…

Statistics Theory · Mathematics 2018-03-02 Dane Taylor , Juan G. Restrepo , Francois G. Meyer

This paper studies the subspace clustering problem. Given some data points approximately drawn from a union of subspaces, the goal is to group these data points into their underlying subspaces. Many subspace clustering methods have been…

Computer Vision and Pattern Recognition · Computer Science 2018-05-24 Canyi Lu , Jiashi Feng , Zhouchen Lin , Tao Mei , Shuicheng Yan

We investigate the potential of quickest detection based on the eigenvalues of the sample covariance matrix for spectrum sensing applications. A simple phase shift keying (PSK) model with additive white Gaussian noise (AWGN), with $1$…

Information Theory · Computer Science 2015-10-14 Martijn Arts , Andreas Bollig , Rudolf Mathar

Biclustering is used for simultaneous clustering of the observations and variables when there is no group structure known \textit{a priori}. It is being increasingly used in bioinformatics, text analytics, etc. Previously, biclustering has…

Methodology · Statistics 2020-09-14 Wangshu Tu , Sanjeena Subedi

For data segmentation in high-dimensional linear regression settings, the regression parameters are often assumed to be sparse segment-wise, which enables many existing methods to estimate the parameters locally via $\ell_1$-regularised…

Methodology · Statistics 2026-05-08 Haeran Cho , Tobias Kley , Housen Li

We establish large sample approximations for an arbitray number of bilinear forms of the sample variance-covariance matrix of a high-dimensional vector time series using $ \ell_1$-bounded and small $\ell_2$-bounded weighting vectors.…

Probability · Mathematics 2020-09-01 Ansgar Steland , Rainer von Sachs

In this paper, we consider the problem of estimating the covariance kernel and its eigenvalues and eigenfunctions from sparse, irregularly observed, noise corrupted and (possibly) correlated functional data. We present a method based on…

Methodology · Statistics 2008-07-09 Debashis Paul , Jie Peng

Sparse PCA is one of the most well-studied problems in high-dimensional statistics. In this problem, we are given samples from a distribution with covariance $\Sigma$, whose top eigenvector $v \in R^d$ is $s$-sparse. Existing sparse PCA…

Machine Learning · Statistics 2026-03-04 Syamantak Kumar , Purnamrita Sarkar , Kevin Tian , Peiyuan Zhang

Repeated measurements are common in many fields, where random variables are observed repeatedly across different subjects. Such data have an underlying hierarchical structure, and it is of interest to learn covariance/correlation at…

Methodology · Statistics 2023-06-13 Sunpeng Duan , Guo Yu , Juntao Duan , Yuedong Wang

A novel method is proposed for detecting changes in the covariance structure of moderate dimensional time series. This non-linear test statistic has a number of useful properties. Most importantly, it is independent of the underlying…

Methodology · Statistics 2021-08-18 Sean Ryan , Rebecca Killick

In this paper, we study the problem of testing the mean vectors of high dimensional data in both one-sample and two-sample cases. The proposed testing procedures employ maximum-type statistics and the parametric bootstrap techniques to…

Statistics Theory · Mathematics 2018-01-23 Jinyuan Chang , Chao Zheng , Wen-Xin Zhou , Wen Zhou