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Related papers: Martingale approximations for random fields

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We develop approximate estimation methods for exponential random graph models (ERGMs), whose likelihood is proportional to an intractable normalizing constant. The usual approach approximates this constant with Monte Carlo simulations,…

Methodology · Statistics 2023-01-11 Angelo Mele , Lingjiong Zhu

The aim of this paper is to represent any continuous local martingale as an almost sure limit of a nested sequence of simple, symmetric random walks, time changed by a discrete quadratic variation process. One basis of this is a similar…

Probability · Mathematics 2010-08-10 Balazs Szekely , Tamas Szabados

We propose, theoretically investigate, and numerically validate an algorithm for the Monte Carlo solution of least-squares polynomial approximation problems in a collocation frame- work. Our method is motivated by generalized Polynomial…

Numerical Analysis · Mathematics 2021-05-04 Akil Narayan , John D. Jakeman , Tao Zhou

Given a sequence of Marcinkiewicz-Zygmund inequalities in $L^2$, we derive approximation theorems and quadrature rules. The derivation is completely elementary and requires only the definition of Marcinkiewicz-Zygmund inequality, Sobolev…

Numerical Analysis · Mathematics 2023-04-18 Karlheinz Gröchenig

We provides some useful estimates for solving martingale representation problem under G-expectations. We also study the corresponding conditions for the existence and uniqueness.

Probability · Mathematics 2010-04-08 Ying Hu , Shige Peng

We construct an objective function that consists of a quadratic approximation term and a penalty term. Thanks to the quadratic approximation, we can deal with various kinds of loss functions into a unified way, and by taking advantage of…

Statistics Theory · Mathematics 2018-11-26 Takumi Suzuki , Nakahiro Yoshida

We introduce basic statistical methods for the extrapolation of stationary random fields. For square integrable fields, we set out basics of the kriging extrapolation techniques. For (non--Gaussian) stable fields, which are known to be…

Probability · Mathematics 2013-06-27 Evgeny Spodarev , Elena Shmileva , Stefan Roth

Random fields are useful mathematical tools for representing natural phenomena with complex dependence structures in space and/or time. In particular, the Gaussian random field is commonly used due to its attractive properties and…

The aim of the paper is to derive for the negative correlation function with a time parameter an asymptotic disjunction of the numerical generalized least-squares estimator of an unknown constant mean of random field in fact the correct…

Numerical Analysis · Computer Science 2015-03-20 Tomasz Suslo

We investigate the conditional distributions of two Banach space valued, jointly Gaussian random variables. In particular, we show that these conditional distributions are again Gaussian and that their means and covariances can be…

Probability · Mathematics 2025-02-25 Ingo Steinwart

We describe an algorithm that, given any full-rank matrix A having fewer rows than columns, can rapidly compute the orthogonal projection of any vector onto the null space of A, as well as the orthogonal projection onto the row space of A,…

Numerical Analysis · Computer Science 2011-05-26 Vladimir Rokhlin , Mark Tygert

Theoretically, the conditional expectation of a square-integrable random variable $Y$ given a $d$-dimensional random vector $X$ can be obtained by minimizing the mean squared distance between $Y$ and $f(X)$ over all Borel measurable…

Computation · Statistics 2023-02-22 Patrick Cheridito , Balint Gersey

Discrete Markov random fields form a natural class of models to represent images and spatial data sets. The use of such models is, however, hampered by a computationally intractable normalising constant. This makes parameter estimation and…

Computation · Statistics 2015-05-25 Haakon Michael Austad , Håkon Tjelmeland

Markov chain Monte Carlo (MCMC) algorithms are simple and extremely powerful techniques to sample from almost arbitrary distributions. The flaw in practice is that it can take a large and/or unknown amount of time to converge to the…

Machine Learning · Computer Science 2014-11-13 Xianghang Liu , Justin Domke

Random Fourier Features (RFF) demonstrate wellappreciated performance in kernel approximation for largescale situations but restrict kernels to be stationary and positive definite. And for non-stationary kernels, the corresponding RFF could…

Machine Learning · Statistics 2021-04-15 Qin Luo , Kun Fang , Jie Yang , Xiaolin Huang

We introduce so-called super/sub-martingale projections as a family of endomorphisms defined on unions of Polish spaces. Such projections allow us to identify martingales as collections of transformations that relate path-valued random…

Quantum Physics · Physics 2026-02-04 Lane P. Hughston , Levent A. Mengütürk

It was shown many times in the literature that a Markov random field is equivalent to a Gibbs random field when all realizations of the field have non-zero probabilities; the proofs are rather complicated. A simpler proof, which is based…

Probability · Mathematics 2016-03-07 Levent Onural

We consider quantile estimation using Markov chain Monte Carlo and establish conditions under which the sampling distribution of the Monte Carlo error is approximately Normal. Further, we investigate techniques to estimate the associated…

Statistics Theory · Mathematics 2018-04-20 Charles Doss , James M. Flegal , Galin L. Jones , Ronald C. Neath

Marginal optima are minima or maxima of a function with many nearly flat directions. In settings with many competing optima, marginal ones tend to attract algorithms and physical dynamics. Often, the important family of marginal attractors…

Disordered Systems and Neural Networks · Physics 2024-12-03 Jaron Kent-Dobias

In this paper we have proposed a median based estimator using known value of some population parameter(s) in simple random sampling. Various existing estimators are shown particular members of the proposed estimator. The bias and mean…

Statistics Theory · Mathematics 2014-08-15 Hemant K. Verma , Rajesh Singh , Florentin Smarandache