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Extracting parameter constraints from cosmological observations requires accurate determination of the covariance matrix for use in the likelihood function. We show here that uncertainties in the elements of the covariance matrix propagate…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Scott Dodelson , Michael D. Schneider

Cosmological parameter estimation requires that the likelihood function of the data is accurately known. Assuming that cosmological large-scale structure power spectra data are multivariate Gaussian-distributed, we show the accuracy of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Andy Taylor , Benjamin Joachimi , Thomas Kitching

In cosmic shear likelihood analyses the covariance is most commonly assumed to be constant in parameter space. Therefore, when calculating the covariance matrix (analytically or from simulations), its underlying cosmology should not…

Astrophysics · Physics 2015-05-13 Tim Eifler , Peter Schneider , Jan Hartlap

Cosmological large-scale structure analyses based on two-point correlation functions often assume a Gaussian likelihood function with a fixed covariance matrix. We study the impact on cosmological parameter estimation of ignoring the…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-21 Darsh Kodwani , David Alonso , Pedro Ferreira

It is known that modeling uncertainties and astrophysical foregrounds can potentially introduce appreciable bias in the deduced values of cosmological parameters. While it is commonly assumed that these uncertainties will be accounted for…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Meir Shimon , Nissan Itzhaki , Yoel Rephaeli

The covariance matrix of the matter power spectrum is a key element of the statistical analysis of galaxy clustering data. Independent realisations of observational measurements can be used to sample the covariance, nevertheless statistical…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-14 Linda Blot , Pier Stefano Corasaniti , Luca Amendola , Thomas D. Kitching

Cosmology contributes a good deal to the investigation of variation of fundamental physical constants. High resolution data is available and allows for detailed analysis over cosmological distances and a multitude of methods were developed.…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-28 M. Wendt , D. Reimers , P. Molaro

Cosmological parameter estimation from forthcoming experiments promise to reach much greater precision than current constraints. As statistical errors shrink, the required control over systematic errors increases. Therefore, models or…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 José Luis Bernal , Nicola Bellomo , Alvise Raccanelli , Licia Verde

The estimation of cosmological parameters from precision observables is an important industry with crucial ramifications for particle physics. This article discusses the statistical methods presently used in cosmological data analysis,…

High Energy Physics - Theory · Physics 2009-12-15 Andrew R Liddle

We investigate the bias and error in estimates of the cosmological parameter covariance matrix, due to sampling or modelling the data covariance matrix, for likelihood width and peak scatter estimators. We show that these estimators do not…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Andy Taylor , Benjamin Joachimi

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

Data analysis from upcoming large galaxy redshift surveys, such as Euclid and DESI will significantly improve constraints on cosmological parameters. To optimally extract the information from these galaxy surveys, it is important to control…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 S. Gouyou Beauchamps , P. Baratta , S. Escoffier , W. Gillard , J. Bel , J. Bautista , C. Carbone

The likelihood function for cosmological parameters, given by e.g. weak lensing shear measurements, depends on contributions to the covariance induced by the nonlinear evolution of the cosmic web. As nonlinear clustering to date has only…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-26 Robert Reischke , Alina Kiessling , Björn Malte Schäfer

We present simulations of a cosmic shear survey and show how the survey geometry influences the accuracy of determination of cosmological parameters. We numerically calculate the full covariance matrices of the two-point statistics \xi_+,…

Astrophysics · Physics 2007-05-23 Martin Kilbinger

We present a joint likelihood analysis of the halo power spectrum and bispectrum in real space. We take advantage of a large set of numerical simulations and of an even larger set of halo mock catalogs to provide a robust estimate of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-23 Andrea Oddo , Federico Rizzo , Emiliano Sefusatti , Cristiano Porciani , Pierluigi Monaco

Covariance matrices are essential cosmological probes of fundamental physics, providing information on numerous fundamental physical parameters and varying with any change in the underlying cosmology. However, this cosmology dependence,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Theodore Steele , Robert Smith , Roisin O'Connor

The advent of large data-set in cosmology has meant that in the past 10 or 20 years our knowledge and understanding of the Universe has changed not only quantitatively but also, and most importantly, qualitatively. Cosmologists rely on data…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Licia Verde

The success of present and future cosmological studies is tied to the ability to detect discrepancies in complex data sets within the framework of a cosmological model. Tensions caused by the presence of unknown systematic effects need to…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 Marco Raveri , Wayne Hu

In this study, we investigate the impact of covariance within uncertainties on the inference of cosmological and astrophysical parameters, specifically focusing on galaxy stellar mass functions derived from the CAMELS simulation suite.…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-30 Yongseok Jo , Shy Genel , Joel Leja , Benjamin Wandelt

The large amount of cosmological data already available (and in the near future) makes necessary the development of efficient numerical codes. Many software products have been implemented to perform cosmological analyses considering one or…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-16 Sandro Dias Pinto Vitenti , Mariana Penna-Lima
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