English
Related papers

Related papers: WISDoM: characterizing neurological timeseries wit…

200 papers

When dealing with electro or magnetoencephalography records, many supervised prediction tasks are solved by working with covariance matrices to summarize the signals. Learning with these matrices requires using Riemanian geometry to account…

A Wishart kernel density estimator (KDE) is introduced for density estimation in the cone of positive definite matrices. The estimator is boundary-aware and mitigates the boundary bias suffered by conventional KDEs, while remaining simple…

Methodology · Statistics 2025-12-10 Léo R. Belzile , Christian Genest , Frédéric Ouimet , Donald Richards

The spectra of empirical correlation matrices, constructed from multivariate data, are widely used in many areas of sciences, engineering and social sciences as a tool to understand the information contained in typically large datasets. In…

Data Analysis, Statistics and Probability · Physics 2021-08-12 Udaysinh T. Bhosale , S. Harshini Tekur , M. S. Santhanam

Random matrix theory has become a cornerstone in modern statistics and data science, providing fundamental tools for understanding high-dimensional covariance structures. Within this framework, the Wishart matrix plays a central role in…

Statistics Theory · Mathematics 2025-11-26 Fengcheng Liu

Generating realistic images to accurately predict changes in the structure of brain MRI is a crucial tool for clinicians. Such applications help assess patients' outcomes and analyze how diseases progress at the individual level. However,…

Image and Video Processing · Electrical Eng. & Systems 2024-06-19 Mattia Litrico , Francesco Guarnera , Valerio Giuffirda , Daniele Ravì , Sebastiano Battiato

Based on a student research project this article gives a short review on Wishart processes. A Wishart procces is a matrix valued continuous time stochastic process with a marginal Wishart distribution. The Wishart distribution is a matrix…

Probability · Mathematics 2012-01-17 Oliver Pfaffel

Positive-definite matrix-variate data is becoming popular in computer vision. The computer vision data descriptors in the form of Region Covariance Descriptors (RCD) are positive definite matrices, which extract the key features of the…

Methodology · Statistics 2022-12-13 Zhou Lan

Wishart random matrix theory is of major importance for the analysis of correlated time series. The distribution of the smallest eigenvalue for Wishart correlation matrices is particularly interesting in many applications. In the complex…

Mathematical Physics · Physics 2013-10-21 Tim Wirtz , Thomas Guhr

Clustering time series into similar groups can improve models by combining information across like time series. While there is a well developed body of literature for clustering of time series, these approaches tend to generate clusters…

Methodology · Statistics 2022-01-19 Benny Ren , Ian Barnett

The space of positive definite symmetric matrices has been studied extensively as a means of understanding dependence in multivariate data along with the accompanying problems in statistical inference. Many books and papers have been…

Statistics Theory · Mathematics 2012-03-16 L. R. Haff , P. T. Kim , J. -Y. Koo , D. St. P. Richards

We introduce and explore a new class of stationary time series models for variance matrices based on a constructive definition exploiting inverse Wishart distribution theory. The main class of models explored is a novel class of stationary,…

Methodology · Statistics 2011-07-27 Emily B. Fox , Mike West

Geostatistical modeling for continuous point-referenced data has been extensively applied to neuroimaging because it produces efficient and valid statistical inference. However, diffusion tensor imaging (DTI), a neuroimaging characterizing…

We provide a compact exact representation for the distribution of the matrix elements of the Wishart-type random matrices $A^\dagger A$, for any finite number of rows and columns of $A$, without any large N approximations. In particular we…

Mathematical Physics · Physics 2008-11-26 Romuald A. Janik , Maciej A. Nowak

Covariance matrices provide a valuable source of information about complex interactions and dependencies within the data. However, from a clustering perspective, this information has often been underutilized and overlooked. Indeed, commonly…

Methodology · Statistics 2024-09-02 Andrea Cappozzo , Alessandro Casa

We present an original and novel method based on random matrix approach that enables to distinguish the respective role of temporal autocorrelations inside given time series and cross correlations between various time series. The proposed…

Data Analysis, Statistics and Probability · Physics 2014-07-18 Michal Sawa , Dariusz Grech

Wasserstein Discriminant Analysis (WDA) is a new supervised method that can improve classification of high-dimensional data by computing a suitable linear map onto a lower dimensional subspace. Following the blueprint of classical Linear…

Machine Learning · Statistics 2018-09-21 Rémi Flamary , Marco Cuturi , Nicolas Courty , Alain Rakotomamonjy

These lecture notes provide a comprehensive, self-contained introduction to the analysis of Wishart matrix moments. This study may act as an introduction to some particular aspects of random matrix theory, or as a self-contained exposition…

Probability · Mathematics 2019-02-12 Adrian N. Bishop , Pierre Del Moral , Angele Niclas

Resting-state functional magnetic resonance imaging (rs-fMRI) is a noninvasive technique pivotal for understanding human neural mechanisms of intricate cognitive processes. Most rs-fMRI studies compute a single static functional…

Neurons and Cognition · Quantitative Biology 2025-02-25 Bishal Thapaliya , Robyn Miller , Jiayu Chen , Yu-Ping Wang , Esra Akbas , Ram Sapkota , Bhaskar Ray , Pranav Suresh , Santosh Ghimire , Vince Calhoun , Jingyu Liu

The correlated Wishart model provides the standard benchmark when analyzing time series of any kind. Unfortunately, the real case, which is the most relevant one in applications, poses serious challenges for analytical calculations. Often…

Mathematical Physics · Physics 2018-08-08 Tim Wirtz , Mario Kieburg , Thomas Guhr

This paper deals with the Elliptical Wishart and Inverse Elliptical Wishart distributions, which play a major role when handling covariance matrices. Similarly to multivariate elliptical distributions, these form a large family of…

Statistics Theory · Mathematics 2024-11-01 Imen Ayadi , Florent Bouchard , Frédéric Pascal
‹ Prev 1 2 3 10 Next ›