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Related papers: Coherence for Random Fields

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Covariance functions are the core of spatial statistics, stochastic processes, machine learning as well as many other theoretical and applied disciplines. The properties of the covariance function at small and large distances determine the…

Statistics Theory · Mathematics 2023-01-16 Alfredo Alegría , Fabián Ramírez , Emilio Porcu

Coherence refers to correlations between field vibrations at two separate points in degrees of freedom such as space, time, and polarisation. In the context of space, coherence theory has been formulated between two transverse positions…

Paradoxically, while the assumptions of second-order stationarity and isotropy appear outdated in light of modern spatial data, they remain remarkably robust in practice, as nonstationary methods often provide marginal improvements in…

Methodology · Statistics 2025-11-07 Federico Blasi , Reinhard Furrer

In modelling time series data coming from different sources, frequencies can easily vary since some variable can be measured at higher frequencies, others, at lower frequencies. Given data measured over spatial units and at varying…

Methodology · Statistics 2025-03-05 Vladimir A. Malabanan , Joseph Ryan G. Lansangan , Erniel B. Barrios

In this paper we explore a covariance spectral modelling strategy for spatial-temporal processes which involves a spectral approach for time but a covariance approach for space.It facilitates the analysis of coherence between the temporal…

Methodology · Statistics 2014-09-17 A. M. Mosammam , J. T. Kent

Multivariate geostatistics is based on modelling all covariances between all possible combinations of two or more variables at any sets of locations in a continuously indexed domain. Multivariate spatial covariance models need to be built…

Methodology · Statistics 2016-10-10 Noel Cressie , Andrew Zammit-Mangion

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

Functional linear regression analysis aims to model regression relations which include a functional predictor. The analog of the regression parameter vector or matrix in conventional multivariate or multiple-response linear regression…

Statistics Theory · Mathematics 2011-02-28 Yichao Wu , Jianqing Fan , Hans-Georg Müller

The theory of quasi-arithmetic means is a powerful tool in the study of covariance functions across space-time. In the present study we use quasi-arithmetic functionals to make inferences about the permissibility of averages of functions…

Probability · Mathematics 2007-06-13 E. Porcu , J. Mateu , G. Christakos

Covariance parameter estimation of Gaussian processes is analyzed in an asymptotic framework. The spatial sampling is a randomly perturbed regular grid and its deviation from the perfect regular grid is controlled by a single scalar…

Statistics Theory · Mathematics 2014-12-09 François Bachoc

Network coherence generally refers to the emergence of simple aggregated dynamical behaviours, despite heterogeneity in the dynamics of the subsystems that constitute the network. In this paper, we develop a general frequency domain…

Systems and Control · Electrical Eng. & Systems 2023-02-17 Hancheng Min , Richard Pates , Enrique Mallada

Spatially-indexed multivariate data appear frequently in geostatistics and related fields including oceanography and environmental science. To take full advantage of this data structure, cross-covariance functions are constructed to…

Methodology · Statistics 2025-03-07 Drew Yarger , Anindya Bhadra

This paper introduces the novel class of modulated cyclostationary processes, a class of non-stationary processes exhibiting frequency coupling, and proposes a method of their estimation from repeated trials. Cyclostationary processes also…

Methodology · Statistics 2012-10-25 Sofia C. Olhede , Hernando Ombao

Quantum coherence is one of the key features that fuels applications for which quantum mechanics exceeds the power of classical physics. This explains the considerable efforts that were undertaken to quantify coherence via quantum resource…

Quantum Physics · Physics 2021-05-19 Michele Masini , Thomas Theurer , Martin B. Plenio

Wavelets provide the flexibility to analyse stochastic processes at different scales. Here, we apply them to multivariate point processes as a means of detecting and analysing unknown non-stationarity, both within and across data streams.…

Methodology · Statistics 2020-11-04 Edward A. K. Cohen , Alexander J. Gibberd

The Coherent Multiplex is formalized and validated as a scalable, real-time system for identifying, analyzing, and visualizing coherence among multiple time series. Its architecture comprises a fast spectral similarity layer based on cosine…

Signal Processing · Electrical Eng. & Systems 2025-08-28 Noah Shore

In this paper, we introduce quantile coherency to measure general dependence structures emerging in the joint distribution in the frequency domain and argue that this type of dependence is natural for economic time series but remains…

Statistics Theory · Mathematics 2018-12-31 Jozef Baruník , Tobias Kley

Building spatial process models that capture nonstationary behavior while delivering computationally efficient inference is challenging. Nonstationary spatially varying kernels (see, e.g., Paciorek, 2003) offer flexibility and richness, but…

Methodology · Statistics 2025-07-01 Sébastien Coube-Sisqueille , Sudipto Banerjee , Benoît Liquet

The Mat\'ern family of covariance functions is currently the most popularly used model in spatial statistics, geostatistics, and machine learning to specify the correlation between two geographical locations based on spatial distance.…

Methodology · Statistics 2023-09-22 Kesen Wang , Sameh Abdulah , Ying Sun , Marc G. Genton

The entrainment between weakly-coupled nonlinear oscillators, as well as between complex signals such as those representing physiological activity, is frequently assessed in terms of whether a stable relationship is detectable between the…

Neurons and Cognition · Quantitative Biology 2019-02-27 Ludovico Minati , Natsue Yoshimura , Mattia Frasca , Stanislaw Drozdz , Yasuharu Koike