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Related papers: Half-Spectral Space-Time Covariance Models

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In this paper we propose a generalization of a class of Gaussian Semiparametric Estimators (GSE) of the fractional differencing parameter for long-range dependent multivariate time series. We generalize a known GSE-type estimator by…

Statistics Theory · Mathematics 2013-05-23 Guilherme Pumi , Sílvia R. C. Lopes

We characterize all multi-dimensional real self-similar Gaussian Markov processes. Three types of covariance matrix functions occur: white-noise type functions, covariances that can be expressed by continuous matrix semigroups, and…

Probability · Mathematics 2025-08-13 Benedict Bauer , Stefan Gerhold

Multivariate spatial field data are increasingly common and whose modeling typically relies on building cross-covariance functions to describe cross-process relationships. An alternative viewpoint is to model the matrix of spectral…

Statistics Theory · Mathematics 2015-05-07 William Kleiber

In many areas of science one aims to estimate latent sub-population mean curves based only on observations of aggregated population curves. By aggregated curves we mean linear combination of functional data that cannot be observed…

Methodology · Statistics 2011-02-15 Ronaldo Dias , Nancy L. Garcia , Alexandra M. Schmidt

We introduce the wavelet scattering spectra which provide non-Gaussian models of time-series having stationary increments. A complex wavelet transform computes signal variations at each scale. Dependencies across scales are captured by the…

Data Analysis, Statistics and Probability · Physics 2023-06-21 Rudy Morel , Gaspar Rochette , Roberto Leonarduzzi , Jean-Philippe Bouchaud , Stéphane Mallat

In this paper we introduce a novel online time series forecasting model we refer to as the pM-GP filter. We show that our model is equivalent to Gaussian process regression, with the advantage that both online forecasting and online…

Machine Learning · Statistics 2015-10-13 Yves-Laurent Kom Samo , Stephen J. Roberts

Gaussian Process State Space Models (GP-SSMs) are a non-parametric model class suitable to represent nonlinear dynamics. They become increasingly popular in data-driven modeling approaches, i.e. when no first-order physics-based models are…

Systems and Control · Computer Science 2018-11-19 Thomas Beckers , Sandra Hirche

Standard sparse pseudo-input approximations to the Gaussian process (GP) cannot handle complex functions well. Sparse spectrum alternatives attempt to answer this but are known to over-fit. We suggest the use of variational inference for…

Machine Learning · Statistics 2015-03-23 Yarin Gal , Richard Turner

The last decades have seen an unprecedented increase in the availability of data sets that are inherently global and temporally evolving, from remotely sensed networks to climate model ensembles. This paper provides a view of statistical…

Statistics Theory · Mathematics 2017-06-29 Emilio Porcu , Alfredo Alegría , Reinhard Furrer

Gaussian processes are popular and flexible models for spatial, temporal, and functional data, but they are computationally infeasible for large datasets. We discuss Gaussian-process approximations that use basis functions at multiple…

Methodology · Statistics 2020-12-22 Matthias Katzfuss , Wenlong Gong

A generator of spatio-temporal pseudo-random Gaussian fields that satisfy the "proportionality of scales" property (Tsyroulnikov, 2001) is presented. The generator is based on a third-order in time stochastic differential equation with a…

Data Analysis, Statistics and Probability · Physics 2018-05-15 Michael Tsyrulnikov , Dmitry Gayfulin

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

Accurately estimating latent velocity vector fields of atmospheric winds is crucial for understanding weather phenomena. Direct measurement of atmospheric winds is costly, especially in the upper atmosphere, so researchers attempt to…

Applications · Statistics 2025-06-12 Youssef Fahmy , Maria Laura Battagliola , Joseph Guinness

The spectral density function describes the second-order properties of a stationary stochastic process on $\mathbb{R}^d$. This paper considers the nonparametric estimation of the spectral density of a continuous-time stochastic process…

Statistics Theory · Mathematics 2023-02-07 Rafail Kartsioukas , Stilian Stoev , Tailen Hsing

As an extension of Gabor signal processing, the covariant Weyl-Heisenberg integral quantization is implemented to transform functions on the eight-dimensional phase space $\left(x,k\right)$ into Hilbertian operators. The…

Quantum Physics · Physics 2022-06-22 Gilles Cohen-Tannoudji , Jean-Pierre Gazeau , Célestin Habonimana , Juma Shabani

Gaussian processes are probabilistic models that are commonly used as functional priors in machine learning. Due to their probabilistic nature, they can be used to capture the prior information on the statistics of noise, smoothness of the…

Computation · Statistics 2024-02-02 Ahmad Farooq , Cristian A. Galvis-Florez , Simo Särkkä

This work is focused on constructing space-time covariance functions through a hierarchical mixture approach that can serve as building blocks for capturing complex dependency structures. This hierarchical mixture approach provides a…

Methodology · Statistics 2025-11-14 Pulong Ma

This thesis focuses on data that has complex spatio-temporal structure and on probabilistic graphical models that learn the structure in an interpretable and scalable manner. We target two research areas of interest: Gaussian graphical…

Machine Learning · Computer Science 2023-01-18 Yu Wang

Gaussian processes are arguably the most important class of spatiotemporal models within machine learning. They encode prior information about the modeled function and can be used for exact or approximate Bayesian learning. In many…

We characterize completely the Gneiting class of space-time covariance functions and give more relaxed conditions on the involved functions. We then show necessary conditions for the construction of compactly supported functions of the…

Methodology · Statistics 2009-02-24 Viktor P. Zastavnyi , Emilio Porcu