English
Related papers

Related papers: Covariances of density probability distribution fu…

200 papers

We show that in a hierarchical clustering model the low-order statistics of the density and the peculiar velocity fields can all be modelled semianalytically for a given cosmology and an initial density perturbation power spectrum $P(k)$.…

Astrophysics · Physics 2015-06-24 H. J. Mo , Y. P. Jing , G. Börner

We trace with analytical methods and in a model parameter independent manner the independent bits of Fisher information of each of the moments of the lognormal distribution, as a now standard prescription for the distribution of the…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-18 Julien Carron

We report a first study of time-dependent Probability Density Functions (PDFs) in the Low-to- High confinement mode (L-H) transition by extending the previous prey-predator-type model (Kim & Diamond, Phys. Rev. Lett. 91, 185006, 2003) to a…

Plasma Physics · Physics 2020-04-29 Eun-jin Kim , Rainer Hollerbach

This article concerns a systemic manifestation of small scale interfacial heterogeneities in large scale quantities of interest to a variety of diverse applications spanning the earth, biological and ecological sciences. Beginning with…

Statistics Theory · Mathematics 2013-12-24 Jorge M. Ramirez , Enrique A. Thomann , Edward C. Waymire

The statistical property of the weak lensing fields is studied quantitatively using the ray-tracing simulations. Motivated by the empirical lognormal model that characterizes the probability distribution function(PDF) of the…

Astrophysics · Physics 2009-11-07 A. Taruya , M. Takada , T. Hamana , I. Kayo , T. Futamase

Small area estimation has become an important tool in official statistics, used to construct estimates of population quantities for domains with small sample sizes. Typical area-level models function as a type of heteroscedastic regression,…

Methodology · Statistics 2022-09-07 Paul A. Parker , Scott H. Holan , Ryan Janicki

We study the one-point probability distribution functions (PDFs) of the peculiar velocity and the density fluctuation in a cosmological fluid. Within the perturbative approach to the structure formation scenario, the effect of ``pressure''…

Astrophysics · Physics 2009-11-11 Takayuki Tatekawa

We consider estimation of covariance matrices and their inverses (a.k.a. precision matrices) for high-dimensional stationary and locally stationary time series. In the latter case the covariance matrices evolve smoothly in time, thus…

Statistics Theory · Mathematics 2014-01-07 Xiaohui Chen , Mengyu Xu , Wei Biao Wu

We study the effect of the non-Gaussianity induced by gravitational evolution upon the statistical properties of absorption in quasar (QSO) spectra. Using the generic hierarchical ansatz and the lognormal approximation we derive the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Dipak Munshi , Peter Coles , Matteo Viel

A probability density function (PDF) of a spatially dependent field provides a means of calculating moments of the field or, equivalently, the proportion of a spatial domain that is mapped to a given set of values. This paper describes a…

Fluid Dynamics · Physics 2025-01-10 Paul M. Mannix , David A. Ham , John Craske

We describe a statistical model to estimate the covariance matrix of matter tracer two-point correlation functions with cosmological simulations. Assuming a fixed number of cosmological simulation runs, we describe how to build a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Christopher B. Morrison , Michael D. Schneider

We introduce the Hessian reweighting of parton distribution functions (PDFs). Similarly to the better-known Bayesian methods, its purpose is to address the compatibility of new data and the quantitative modifications they induce within an…

High Energy Physics - Phenomenology · Physics 2015-06-18 Hannu Paukkunen , Pia Zurita

Current and forthcoming cosmological data analyses share the challenge of huge datasets alongside increasingly tight requirements on the precision and accuracy of extracted cosmological parameters. The community is becoming increasingly…

Instrumentation and Methods for Astrophysics · Physics 2014-12-17 Benjamin Joachimi , Andy Taylor

In the presence of modeling errors, the mainstream Bayesian methods seldom give a realistic account of uncertainties as they commonly underestimate the inherent variability of parameters. This problem is not due to any misconception in the…

Applications · Statistics 2020-05-19 Omid Sedehi , Costas Papadimitriou , Lambros S. Katafygiotis

The classical stochastic model of cosmology recently developed by us is reconsidered. In that approach the parameter $w$ defined by the equation of state $p=w{\rho}$ was taken to be fluctuating with mean zero and we compared the theoretical…

Astrophysics · Physics 2009-11-07 Moncy V. John , C. Sivakumar , K. Babu Joseph

Molecular dynamics (MD) simulations are powerful tools for elucidating the macroscopic physical properties of materials from microscopic atomic behaviors. However, the massive, high-dimensional datasets generated by MD simulations pose a…

Applications · Statistics 2026-03-19 Yusuke Ono , Takumi Sato , Kenji Yasuoka , Linyu Peng

Stochastic resetting is a rapidly developing topic in the field of stochastic processes and their applications. It denotes the occasional reset of a diffusing particle to its starting point and effects, inter alia, optimal first-passage…

Statistical Mechanics · Physics 2023-05-25 C. Di Bello , A. V. Chechkin , A. K. Hartmann , Z. Palmowski , R. Metzler

This paper introduces a novel nonparametric method for estimating high-dimensional dynamic covariance matrices with multiple conditioning covariates, leveraging random forests and supported by robust theoretical guarantees. Unlike…

Machine Learning · Statistics 2025-05-20 Shuguang Yu , Fan Zhou , Yingjie Zhang , Ziqi Chen , Hongtu Zhu

Variational Bayesian inference is an important machine-learning tool that finds application from statistics to robotics. The goal is to find an approximate probability density function (PDF) from a chosen family that is in some sense…

Machine Learning · Computer Science 2022-09-27 Timothy D. Barfoot , Gabriele M. T. D'Eleuterio

Continuously indexed datasets with multiple variables have become ubiquitous in the geophysical, ecological, environmental and climate sciences, and pose substantial analysis challenges to scientists and statisticians. For many years,…

Methodology · Statistics 2015-07-30 Marc G. Genton , William Kleiber