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Related papers: A generalized spatial sign covariance matrix

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The spectral form factor (SFF) plays a crucial role in revealing the statistical properties of energy level distributions in complex systems. It is one of the tools to diagnose quantum chaos and unravel the universal dynamics therein. The…

Statistical Mechanics · Physics 2024-01-17 Zhiyang Wei , Chengming Tan , Ren Zhang

We consider four main goals when fitting spatial linear models: 1) estimating covariance parameters, 2) estimating fixed effects, 3) kriging (making point predictions), and 4) block-kriging (predicting the average value over a region). Each…

Methodology · Statistics 2023-05-16 Jay M. Ver Hoef , Michael Dumelle , Matt Higham , Erin E. Peterson , Daniel J. Isaak

In this paper, we consider the problem of testing the mean vector in the high dimensional settings. We proposed a new robust scalar transform invariant test based on spatial sign. The proposed test statistic is asymptotically normal under…

Methodology · Statistics 2015-06-30 Long Feng , Fasheng Sun

Multivariate spatial-statistical models are often used when modeling environmental and socio-demographic processes. The most commonly used models for multivariate spatial covariances assume both stationarity and symmetry for the…

Methodology · Statistics 2021-05-11 Quan Vu , Andrew Zammit-Mangion , Noel Cressie

Human migration exhibits complex spatiotemporal dependence driven by environmental and socioeconomic forces. Modeling such patterns at scale requires methods that accommodate many random effects while remaining feasible when raw data or…

Methodology · Statistics 2026-05-29 Lida Chalangar Jalili Dehkharghani , Li-Hsiang Lin

In the hyperspectral image classification (HSIC) task, the most commonly used model validation paradigm is partitioning the training-test dataset through pixel-wise random sampling. By training on a small amount of data, the deep learning…

Computer Vision and Pattern Recognition · Computer Science 2024-10-23 Enzhe Zhao , Zhichang Guo , Shengzhu Shi , Yao Li , Jia Li , Dazhi Zhang

The cosine transforms of functions on the unit sphere play an important role in convex geometry, the Banach space theory, stochastic geometry and other areas. Their higher-rank generalization to Grassmann manifolds represents an interesting…

Functional Analysis · Mathematics 2007-05-23 E. Ournycheva , B. Rubin

The versatility of self-attention mechanism earned transformers great success in almost all data modalities, with limitations on the quadratic complexity and difficulty of training. To apply transformers across different data modalities,…

Machine Learning · Computer Science 2024-08-20 Viet Anh Nguyen , Minh Lenhat , Khoa Nguyen , Duong Duc Hieu , Dao Huu Hung , Truong Son Hy

Suppose that $\gamma$ and $\sigma$ are two continuous bounded variation paths which take values in a finite-dimensional inner product space $V$. Recent papers have introduced the truncated and the untruncated signature kernel of $\gamma$…

Probability · Mathematics 2024-02-06 Thomas Cass , Terry Lyons , Xingcheng Xu

Representation learning is a fundamental but challenging problem, especially when the distribution of data is unknown. We propose a new representation learning method, termed Structure Transfer Machine (STM), which enables feature learning…

Machine Learning · Computer Science 2019-08-06 Baochang Zhang , Lian Zhuo , Ze Wang , Jungong Han , Xiantong Zhen

In this paper, we prove a universality result of convergence for a bivariate random process defined by the eigenvectors of a sample covariance matrix. Let $V_n=(v_{ij})_{i \leq n,\, j\leq m}$ be a $n\times m$ random matrix, where $(n/m)\to…

Probability · Mathematics 2013-06-19 Ali Bouferroum

We propose a conditional independence (CI) test based on a new measure, the \emph{spectral generalized covariance measure} (SGCM). The SGCM is constructed by expressing the squared norm of the conditional cross-covariance operator in…

Methodology · Statistics 2026-04-07 Ryunosuke Miyazaki , Yoshimasa Uematsu

Based on standardized vector and globally normalized weight matrix, Moran's index of spatial autocorrelation analysis has been expressed as a formula of quadratic form. Further, based on this formula, an inner product equation and outer…

Methodology · Statistics 2023-05-02 Yanguang Chen

An approach is presented for the inversion of simulated and experimental in-plane, co-polarized light scattering data in p and s polarization to obtain the normalized surface-height autocorrelation function and the rms-roughness of a…

Optics · Physics 2024-06-13 I. Simonsen , J. B. Kryvi , A. A. Maradudin

Support Vector Machines (SVMs) with various kernels have played dominant role in machine learning for many years, finding numerous applications. Although they have many attractive features interpretation of their solutions is quite…

Machine Learning · Computer Science 2019-01-29 Tomasz Maszczyk , Włodzisław Duch

State space models (SSMs) are a flexible approach to modeling complex time series. However, inference in SSMs is often computationally prohibitive for long time series. Stochastic gradient MCMC (SGMCMC) is a popular method for scalable…

Machine Learning · Statistics 2019-07-11 Christopher Aicher , Yi-An Ma , Nicholas J. Foti , Emily B. Fox

The purpose of this report is in examining the generalization performance of Support Vector Machines (SVM) as a tool for pattern recognition and object classification. The work is motivated by the growing popularity of the method that is…

Machine Learning · Computer Science 2014-12-16 Eugene Borovikov

Covariance functions and variograms play a fundamental role in exploratory analysis and statistical modelling of spatial and spatio-temporal datasets. In this paper, we construct a new class of spatial covariance functions using the Fourier…

Methodology · Statistics 2021-11-16 Mohammad Ghorbani , Jorge Mateu

Scanning superconducting quantum interference device microscopy (SSM) is a scanning probe technique that images local magnetic flux, which allows for mapping of magnetic fields with high field and spatial accuracy. Many studies involving…

Instrumentation and Detectors · Physics 2018-01-17 P. Reith , X. Renshaw Wang , H. Hilgenkamp

Recently the general linear transformation for point rotation coordinate frames was considered. A distinguishing feature of the frame, in contrast to the Cartesian one, is the existence of the rotation axis at every point. The frame…

Optics · Physics 2009-01-28 Boris V. Gisin