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Varying domains and biased datasets can lead to differences between the training and the target distributions, known as covariate shift. Current approaches for alleviating this often rely on estimating the ratio of training and target…

Machine Learning · Statistics 2020-10-27 Bijan Mazaheri , Siddharth Jain , Jehoshua Bruck

The one-point probability distribution function (PDF) is a powerful summary statistic for non-Gaussian cosmological fields, such as the weak lensing (WL) convergence reconstructed from galaxy shapes or cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-04 Leander Thiele , J. Colin Hill , Kendrick M. Smith

Context: Statistical properties of the cosmic density fields are to a large extent encoded in the shape of the one-point density probability distribution functions (PDF). In order to successfully exploit such observables, a detailed…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-20 Francis Bernardeau

The Riemannian geometry of covariance matrices has been essential to several successful applications, in computer vision, biomedical signal and image processing, and radar data processing. For these applications, an important ongoing…

Statistics Theory · Mathematics 2017-05-15 Salem Said , Hatem Hajri , Lionel Bombrun , Baba C. Vemuri

Heckman selection model is the most popular econometric model in analysis of data with sample selection. However, selection models with Normal errors cannot accommodate heavy tails in the error distribution. Recently, Marchenko and Genton…

Computation · Statistics 2014-01-08 Peng Ding

We propose a model-based geostatistical approach to deal with regionalized compositions. We combine the additive-log-ratio transformation with multivariate geostatistical models whose covariance matrix is adapted to take into account the…

Many statistical models in cosmology can be simulated forwards but have intractable likelihood functions. Likelihood-free inference methods allow us to perform Bayesian inference from these models using only forward simulations, free from…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 Justin Alsing , Benjamin Wandelt , Stephen Feeney

In this paper, we develop local expansions for the ratio of the centered matrix-variate $T$ density to the centered matrix-variate normal density with the same covariances. The approximations are used to derive upper bounds on several…

Statistics Theory · Mathematics 2022-11-18 Frédéric Ouimet

We investigate whether a Gaussian likelihood is sufficient to obtain accurate parameter constraints from a Euclid-like combined tomographic power spectrum analysis of weak lensing, galaxy clustering and their cross-correlation. Testing its…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-03 Robin E. Upham , Michael L. Brown , Lee Whittaker

The interpretation of cosmological observables requires the use of increasingly sophisticated theoretical models. Since these models are becoming computationally very expensive and display non-trivial uncertainties, the use of standard…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Marcos Pellejero-Ibañez , Raul E. Angulo , Giovanni Aricó , Matteo Zennaro , Sergio Contreras , Jens Stücker

Super-sample covariance (SSC) is the dominant source of statistical error on large scale structure (LSS) observables for both current and future galaxy surveys. In this work, we concentrate on the SSC of cluster counts, also known as sample…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-06 Fabien Lacasa , Marcos Lima , Michel Aguena

Focusing on the well motivated aperture mass statistics $\Map$, we study the possibility of constraining cosmological parameters using future space based SNAP class weak lensing missions. Using completely analytical results we construct the…

Astrophysics · Physics 2007-05-23 Dipak Munshi , Patrick Valageas

Multivariate hypergeometric distribution arises frequently in elementary statistics and probability courses, for simultaneously studying the occurence law of specified events, when sampling without replacement from a finite population with…

Statistics Theory · Mathematics 2021-01-05 X. G. Duan

Diffusion models can generate a variety of high-quality images by modeling complex data distributions. Trained diffusion models can also be very effective image priors for solving inverse problems. Most of the existing diffusion-based…

Image and Video Processing · Electrical Eng. & Systems 2025-09-01 Nebiyou Yismaw , Ulugbek S. Kamilov , M. Salman Asif

Gaussian graphical models typically assume a homogeneous structure across all subjects, which is often restrictive in applications. In this article, we propose a weighted pseudo-likelihood approach for graphical modeling which allows…

Methodology · Statistics 2023-03-17 Sutanoy Dasgupta , Peng Zhao , Jacob Helwig , Prasenjit Ghosh , Debdeep Pati , Bani K. Mallick

Context: Two-point correlation functions are used throughout cosmology as a measure for the statistics of random fields. When used in Bayesian parameter estimation, their likelihood function is usually replaced by a Gaussian approximation.…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-07 David Keitel , Peter Schneider

Counts-in-cells (CIC) measurements contain a wealth of cosmological information yet are seldom used to constrain theories. Although we can predict the shape of the distribution for a given cosmology, to fit a model to the observed CIC…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-02 Andrew Repp , István Szapudi

Forecasting multivariate time series is a computationally intensive task challenged by extreme or redundant samples. Recent resampling methods aim to increase training efficiency by reweighting samples based on their running losses.…

Machine Learning · Computer Science 2024-06-21 Jiang You , Arben Cela , René Natowicz , Jacob Ouanounou , Patrick Siarry

Using 1000 ray-tracing simulations for a {\Lambda}-dominated cold dark model in Sato et al. (2009), we study the covariance matrix of cosmic shear correlation functions, which is the standard statistics used in the previous measurements.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Masanori Sato , Masahiro Takada , Takashi Hamana , Takahiko Matsubara

We explore strategies to extract cosmological constraints from a joint analysis of cosmic shear, galaxy-galaxy lensing, galaxy clustering, cluster number counts and cluster weak lensing. We utilize the CosmoLike software to simulate results…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 Elisabeth Krause , Tim Eifler