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In this work, we study a family of wireless channel simulation models called geometry-based stochastic channel models (GBSCMs). Compared to more complex ray-tracing simulation models, GBSCMs do not require an extensive characterization of…

Information Theory · Computer Science 2018-06-12 Paul Ferrand

The paper studies the problem of filtering a discrete-time linear system observed by a network of sensors. The sensors share a common communication medium to the estimator and transmission is bit and power budgeted. Under the assumption of…

Information Theory · Computer Science 2009-10-07 S. Kar , B. Sinopoli , J. M. F. Moura

We address high dimensional covariance estimation for elliptical distributed samples, which are also known as spherically invariant random vectors (SIRV) or compound-Gaussian processes. Specifically we consider shrinkage methods that are…

Methodology · Statistics 2015-05-20 Yilun Chen , Ami Wiesel , Alfred O. Hero

This paper presents a unifying theory of Linear second order systems that allows time-varying and time invariant systems to be treated in the same way for the first time. In the process, a transformation is given that diagonalizes an…

Systems and Control · Electrical Eng. & Systems 2026-04-24 Douglas R. Frey

In this paper we develop a new approach to nonlinear stochastic partial differential equations with Gaussian noise. Our aim is to provide an abstract framework which is applicable to a large class of SPDEs and includes many important cases…

Functional Analysis · Mathematics 2022-05-02 Antonio Agresti , Mark Veraar

We tackle covariance estimation in low-sample scenarios, employing a structured covariance matrix with shrinkage methods. These involve convexly combining a low-bias/high-variance empirical estimate with a biased regularization estimator,…

Instrumentation and Methods for Astrophysics · Physics 2024-06-28 Olivier Flasseur , Eric Thiébaut , Loïc Denis , Maud Langlois

Stochastic linear modelling proposed in Tissot, M\'emin & Cavalieri (J. Fluid Mech., vol. 912, 2021, A51) is based on classical conservation laws subject to a stochastic transport. Once linearised around the mean flow and expressed in the…

Fluid Dynamics · Physics 2022-07-27 Gilles Tissot , André Cavalieri , Etienne Mémin

Stochastic flows of an advective-diffusive nature are ubiquitous in physical sciences. Of particular interest is the problem to reconcile observed marginal distributions with a given prior posed by E. Schrodinger in 1932/32 and known as the…

Mathematical Physics · Physics 2021-08-09 Yongxin Chen , Tryphon T. Georgiou , Michele Pavon

Multivariate time series present many challenges, especially when they are high dimensional. The paper's focus is twofold. First, we address the subject of consistently estimating the autocovariance sequence; this is a sequence of matrices…

Statistics Theory · Mathematics 2015-06-03 Carsten Jentsch , Dimitris N. Politis

Many modern time series arise on networks, where each component is attached to a node and interactions follow observed edges. Classical time-varying parameter VARs (TVP-VARs) treat all series symmetrically and ignore this structure, while…

Methodology · Statistics 2025-12-23 Marios Papamichalis , Regina Ruane , Theofanis Papamichalis

We consider the problem of steering an initial probability density for the state vector of a linear system to a final one, in finite time, using minimum energy control. In the case where the dynamics correspond to an integrator ($\dot x(t)…

Optimization and Control · Mathematics 2015-02-05 Yongxin Chen , Tryphon Georgiou , Michele Pavon

In this paper, nonlinear model reduction for power systems is performed by the balancing of empirical controllability and observability covariances that are calculated around the operating region. Unlike existing model reduction methods,…

Systems and Control · Computer Science 2016-08-30 Junjian Qi , Jianhui Wang , Hui Liu , Aleksandar D. Dimitrovski

This paper considers regularizing a covariance matrix of $p$ variables estimated from $n$ observations, by hard thresholding. We show that the thresholded estimate is consistent in the operator norm as long as the true covariance matrix is…

Statistics Theory · Mathematics 2009-01-21 Peter J. Bickel , Elizaveta Levina

We study the tunneling through an oscillating delta barrier. Using time periodicity of the model, the time-dependent Schr\"odinger equation is reduced to a simple but infinite matrix equation. Employing Toeplitz matrices methods, the…

Quantum Physics · Physics 2009-10-30 E. Eisenberg , Y. Ashkenazy

The paper investigates the problem of estimating the state of a time-varying system with a linear measurement model; in particular, the paper considers the case where the number of measurements available can be smaller than the number of…

Systems and Control · Electrical Eng. & Systems 2021-04-07 Guido Cavraro , Emiliano Dall'Anese , Joshua Comden , Andrey Bernstein

This paper considers the problem of steering the state distribution of a nonlinear stochastic system from an initial Gaussian to a terminal distribution with a specified mean and covariance, subject to probabilistic path constraints. An…

Optimization and Control · Mathematics 2019-09-16 Jack Ridderhof , Kazuhide Okamoto , Panagiotis Tsiotras

Quantum counterparts of Schrodinger's classical bridge problem have been around for the better part of half a century. During that time, several quantum approaches to this multifaceted classical problem have been introduced. In the present…

Quantum Physics · Physics 2025-03-11 Olga Movilla Miangolarra , Ralph Sabbagh , Tryphon T. Georgiou

In this work we explore a new framework for approximate Bayesian inference in large datasets based on stochastic control (i.e. Schr\"odinger bridges). We advocate stochastic control as a finite time and low variance alternative to popular…

We present a self-contained and comprehensive study of the Fisher-Rao space of matrix-valued non-commutative probability measures, and of the related Hellinger space. Our non-commutative Fisher-Rao space is a natural generalization of the…

Functional Analysis · Mathematics 2021-01-05 Léonard Monsaingeon , Dmitry Vorotnikov

We model time-varying network data as realizations from multivariate Gaussian distributions with precision matrices that change over time. To facilitate parameter estimation, we require not only that each precision matrix at any given time…

Methodology · Statistics 2022-03-11 Jie Jian , Peijun Sang , Mu Zhu