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Related papers: Approximative Covariance Interpolation

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We discuss the interpolation of the electric and magnetic fields within a charge-conserving Particle-In-Cell scheme. The choice of the interpolation procedure for the fields acting on a particle can be constrained by analyzing conservation…

Plasma Physics · Physics 2012-09-14 Igor V. Sokolov

Cooperative spectrum sensing based on the limiting eigenvalue ratio of the covariance matrix offers superior detection performance and overcomes the noise uncertainty problem. While an exact expression exists, it is complex and multiple…

Signal Processing · Electrical Eng. & Systems 2019-09-04 Fuhui Zhou , Norman C. Beaulieu

Inference methods are often formulated as variational approximations: these approximations allow easy evaluation of statistics by marginalization or linear response, but these estimates can be inconsistent. We show that by introducing…

Machine Learning · Statistics 2017-04-27 Jack Raymond , Federico Ricci-Tersenghi

Welch's method provides an estimator of the power spectral density that is statistically consistent. This is achieved by averaging over periodograms calculated from overlapping segments of a time series. For a finite length time series,…

Methodology · Statistics 2024-04-12 Lachlan C. Astfalck , Adam M. Sykulski , Edward J. Cripps

Interferometric phase linking (IPL) has become a prominent technique for processing images of areas containing distributed scaterrers in SAR interferometry. Traditionally, IPL consists in estimating consistent phase differences between all…

Applications · Statistics 2024-03-14 Phan Viet Hoa Vu , Arnaud Breloy , Frédéric Brigui , Yajing Yan , Guillaume Ginolhac

With the increasing penetration of high-frequency sensors across a number of biological and physical systems, the abundance of the resulting observations offers opportunities for higher statistical accuracy of down-stream estimates, but…

Optimization and Control · Mathematics 2020-11-06 Shushu Zhang , Vivak Patel

In this paper, an alternative approximation to the innovation method is introduced for the parameter estimation of diffusion processes from partial and noisy observations. This is based on a convergent approximation to the first two…

Optimization and Control · Mathematics 2013-12-19 J. C. Jimenez

A fundamental building block for supporting better utilization of radio spectrum involves predicting the impact that an emitter will have at different geographic locations. To this end, fixed sensors can be deployed to spatially sample the…

Computational Engineering, Finance, and Science · Computer Science 2016-11-14 Shweta Sagari , Larry Greenstein , Wade Trappe

Estimation of the covariance structure of spatial processes is of fundamental importance in spatial statistics. In the literature, several non-parametric and semi-parametric methods have been developed to estimate the covariance structure…

Methodology · Statistics 2016-11-06 Shu Yang , Zhengyuan Zhu

The mutual intensity and its equivalent phase-space representations quantify an optical field's state of coherence and are important tools in the study of light propagation and dynamics, but they can only be estimated indirectly from…

Optics · Physics 2017-11-16 Chenglong Bao , George Barbastathis , Hui Ji , Zuowei Shen , Zhengyun Zhang

We propose a data-driven method to learn the time-dependent probability density of a multivariate stochastic process from sample paths, assuming that the initial probability density is known and can be evaluated. Our method uses a novel…

Machine Learning · Statistics 2025-06-19 Agnimitra Dasgupta , Javier Murgoitio-Esandi , Ali Fardisi , Assad A Oberai

The estimation of the covariance function of a stochastic process, or signal, is of integral importance for a multitude of signal processing applications. In this work, we derive closed-form expressions for the variance of covariance…

Signal Processing · Electrical Eng. & Systems 2021-10-05 Filip Elvander , Johan Karlsson

On a high-frequency scale the time series are not homogeneous, therefore standard correlation measures can not be directly applied to the raw data. There are two ways to deal with this problem. The time series can be homogenised through an…

Statistical Mechanics · Physics 2016-08-31 Ovidiu Precup , Giulia Iori

Estimating the ratio of two probability densities from finitely many samples, is a central task in machine learning and statistics. In this work, we show that a large class of kernel methods for density ratio estimation suffers from error…

Machine Learning · Computer Science 2024-06-04 Lukas Gruber , Markus Holzleitner , Johannes Lehner , Sepp Hochreiter , Werner Zellinger

Gaussian time-series models are often specified through their spectral density. Such models present several computational challenges, in particular because of the non-sparse nature of the covariance matrix. We derive a fast approximation of…

Computation · Statistics 2012-11-20 Nicolas Chopin , Judith Rousseau , Brunero Liseo

Interpolation models are critical for a wide range of applications, from numerical optimization to artificial intelligence. The reliability of the provided interpolated value is of utmost importance, and it is crucial to avoid the…

Numerical Analysis · Mathematics 2023-08-15 Daniele Peri

We present a general form of the iteration and interpolation process used in implicit particle filters. Implicit filters are based on a pseudo-Gaussian representation of posterior densities, and are designed to focus the particle paths so…

Numerical Analysis · Mathematics 2009-10-20 Alexandre J. Chorin , Xuemin Tu

We propose a physics-based regularization technique for function learning, inspired by statistical mechanics. By drawing an analogy between optimizing the parameters of an interpolator and minimizing the energy of a system, we introduce…

Machine Learning · Computer Science 2025-08-20 Abhisek Ganguly , Alessandro Gabbana , Vybhav Rao , Sauro Succi , Santosh Ansumali

The problem of mean square optimal estimation of linear functionals which depend on the unobserved values of a periodically correlated stochastic sequence is considered. The estimates are based on observations of the sequence with a noise.…

Statistics Theory · Mathematics 2020-02-12 Iryna Golichenko , Mikhail Moklyachuk

We consider near-critical two-dimensional statistical systems at phase coexistence on the half plane with boundary conditions leading to the formation of a droplet separating coexisting phases. General low-energy properties of…

Statistical Mechanics · Physics 2022-12-02 Alessio Squarcini , Antonio Tinti