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Expanding on neural operators, we propose a novel framework for stochastic process learning across arbitrary domains. In particular, we develop operator flow matching (OFM) for learning stochastic process priors on function spaces. OFM…

Machine Learning · Computer Science 2025-10-14 Yaozhong Shi , Zachary E. Ross , Domniki Asimaki , Kamyar Azizzadenesheli

Generalizing both Substable FSMs and Indicator FSMs, we introduce alpha-stabilized subordination, a procedure which produces new FSMs (H-sssi symmetric stable processes) from old ones. We extend these processes to isotropic stable fields…

Probability · Mathematics 2012-06-28 Paul Jung

In this paper, we study the problem of inferring time-varying Markov random fields (MRF), where the underlying graphical model is both sparse and changes sparsely over time. Most of the existing methods for the inference of time-varying…

Machine Learning · Computer Science 2021-02-09 Salar Fattahi , Andres Gomez

We introduce a new class of nonstationary kernels, which we derive as covariance functions of a novel family of stochastic processes we refer to as string Gaussian processes (string GPs). We construct string GPs to allow for multiple types…

Machine Learning · Statistics 2015-06-09 Yves-Laurent Kom Samo , Stephen Roberts

In this paper, we consider a fractional Poisson random field (FPRF) on positive plane. It is defined as a process whose one dimensional distribution is the solution of a system of fractional partial differential equations. A time-changed…

Probability · Mathematics 2024-07-23 K. K. Kataria , P. Vishwakarma

We consider the non-local operator of variable order as follows $$Lf(x)= \int_{\R^d\setminus\{0\}}\big(f(x+z)-f(x)-\<\nabla f(x),z\> \I_{\{|z|\le 1\}}\big)\frac{n(x,z)}{|z|^{d+\alpha(x)}}\,dz.$$ Under mild conditions on $\alpha(x)$ and…

Probability · Mathematics 2014-04-04 Dejun Luo , Jian Wang

Operator learning is a data-driven approximation of mappings between infinite-dimensional function spaces, such as the solution operators of partial differential equations. Kernel-based operator learning can offer accurate, theoretically…

Machine Learning · Computer Science 2025-12-22 Xinyue Yu , Hayden Schaeffer

An operator fractional Brownian field (OFBF) is a Gaussian, stationary increment R^n-valued random field on R^m that satisfies the operator self-similarity property {X(c^E t)}_{t in R^m} L= {c^H X(t)}_{t in R^m}, c > 0, for two matrix…

Probability · Mathematics 2016-09-06 Gustavo Didier , Mark M. Meerschaert , Vladas Pipiras

Gaussian Conditional Random Fields (GCRF), as a structured regression model, is designed to achieve higher regression accuracy than unstructured predictors at the expense of execution time, taking into account the objects similarities and…

Machine Learning · Computer Science 2019-09-04 Milan Bašić , Branko Arsić , Zoran Obradović

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

The two-parameter tempered Hermite field modifies the power law kernel in the moving average representation of the Hermite field by adding an exponential tempering. This paper develops the basic theory of two-parameter tempered Hermite…

Probability · Mathematics 2022-04-05 Atef Lechiheb

Gaussian processes have been successful in both supervised and unsupervised machine learning tasks, but their computational complexity has constrained practical applications. We introduce a new approximation for large-scale Gaussian…

Machine Learning · Computer Science 2015-11-03 David A. Moore , Stuart J. Russell

We define and study fractional versions of the well-known Gamma subordinator $\Gamma :=\{\Gamma (t),$ $t\geq 0\},$ which are obtained by time-changing $% \Gamma $ by means of an independent stable subordinator or its inverse. Their…

Probability · Mathematics 2013-05-09 Luisa Beghin

In this paper a new approach for constructing \emph{multivariate} Gaussian random fields (GRFs) using systems of stochastic partial differential equations (SPDEs) has been introduced and applied to simulated data and real data. By solving a…

Methodology · Statistics 2013-07-08 Xiangping Hu , Daniel Simpson , Finn Lindgren , Håvard Rue

We describe new families of random fractals, referred to as "V-variable", which are intermediate between the notions of deterministic and of standard random fractals. The parameter V describes the degree of "variability" : at each…

Probability · Mathematics 2007-05-23 Michael Barnsley , John E. Hutchinson , Örjan Stenflo

Location of non-stationary forced oscillation (FO) sources can be a challenging task, especially in cases under resonance condition with natural system modes, where the magnitudes of the oscillations could be greater in places far from the…

Systems and Control · Electrical Eng. & Systems 2022-03-22 Pablo Gill Estevez , Pablo Marchi , Francisco Messina , Cecilia Galarza

The multivariate version of the Mixed Tempered Stable is proposed. It is a generalization of the Normal Variance Mean Mixtures. Characteristics of this new distribution and its capacity in fitting tails and capturing dependence structure…

Statistical Finance · Quantitative Finance 2016-10-04 Asmerilda Hitaj , Friedrich Hubalek , Lorenzo Mercuri , Edit Rroji

Fractional calculus provides a rigorous mathematical framework to describe anomalous stochastic processes by generalizing the notion of classical differential equations to their fractional-order counterparts. By introducing the fractional…

Numerical Analysis · Mathematics 2018-06-04 Ehsan Kharazmi , Mohsen Zayernouri

Autoregressive tempered fractionally integrated moving average (ARTFIMA) time series is a useful model for velocity data in turbulence flows. In this paper, we obtain an invariance principle for the partial sum of an ARTFIMA process. The…

Probability · Mathematics 2014-08-20 Farzad Sabzikar

We derive general properties of anomalous diffusion and nonexponential relaxation from the theory of tempered \alpha-stable processes. Its most important application is to overcome the infinite-moment difficulty for the \alpha-stable random…

Statistical Mechanics · Physics 2011-11-15 Aleksander Stanislavsky , Karina Weron , Aleksander Weron