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相关论文: Semi-analytical covariance matrices for two-point …

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A general non-Gaussian semiparametric model is adopted to characterize the measurement vectors, i.e.\ the \textit{snapshots}, collected by a linear array. Moreover, the recently derived \textit{robust semiparametric efficient} $R$-estimator…

信号处理 · 电气工程与系统科学 2020-04-29 Stefano Fortunati , Alexandre Renaux , Frédéric Pascal

Detection of parity violation on cosmological scales would have profound implications for fundamental physics. Motivated in part by recent measurements of parity-odd four-point correlation functions in BOSS and DESI luminous red galaxy…

宇宙学与河外天体物理 · 物理学 2026-04-08 Zucheng Gao , Marina S. Cagliari , Azadeh Moradinezhad Dizgah , Zvonimir Vlah

We present here the cosmo-SLICS, a new suite of simulations specially designed for the analysis of current and upcoming weak lensing data beyond the standard two-point cosmic shear. We sample the $[\Omega_{\rm m}, \sigma_8, h, w_0]$…

宇宙学与河外天体物理 · 物理学 2019-11-20 Joachim Harnois-Deraps , Benjamin Giblin , Benjamin Joachimi

An accurate covariance matrix is essential for obtaining reliable cosmological results when using a Gaussian likelihood. In this paper we study the covariance of pseudo-$C_\ell$ estimates of tomographic cosmic shear power spectra. Using two…

We derive in this paper expressions for the covariance matrix of the cosmic shear two-point correlation functions which are readily applied to any survey geometry. Furthermore, we consider the more special case of a simple survey geometry…

天体物理学 · 物理学 2009-11-07 Peter Schneider , Ludovic van Waerbeke , Martin Kilbinger , Yannick Mellier

Upcoming cosmic microwave background (CMB) lensing measurements and tomographic galaxy surveys are expected to provide us with high-precision data sets in the coming years, thus paving the way for fruitful cross-correlation analyses. In…

宇宙学与河外天体物理 · 物理学 2022-07-27 Priyesh Chakraborty , Shu-Fan Chen , Cora Dvorkin

We derive a semi-analytical extension of the spherical collapse model of structure formation that takes account of the effects of deviations from spherical symmetry and shell crossing which are important in the non-linear regime. Our model…

天体物理学 · 物理学 2008-11-26 Douglas J. Shaw , David F. Mota

We model the two-point correlation function of galaxies in a cold dark matter Universe by combining two powerful theoretical tools - dissipationless N-body simulations of dark matter clustering (specifically the GIF simulations carried out…

天体物理学 · 物理学 2007-05-23 A. J. Benson , S. Cole , C. S. Frenk , C. M. Baugh , C. G. Lacey

We consider the classical problem of estimating the covariance matrix of a subgaussian distribution from i.i.d. samples in the novel context of coarse quantization, i.e., instead of having full knowledge of the samples, they are quantized…

信息论 · 计算机科学 2022-04-25 Sjoerd Dirksen , Johannes Maly , Holger Rauhut

We constrain the linear and quadratic bias parameters from the configuration dependence of the three-point correlation function (3PCF) in both redshift and projected space, utilizing measurements of spectroscopic galaxies in the Sloan…

We study online inference and asymptotic covariance estimation for the stochastic gradient descent (SGD) algorithm. While classical methods (such as plug-in and batch-means estimators) are available, they either require inaccessible…

机器学习 · 统计学 2026-04-24 Ziyang Wei , Wanrong Zhu , Jingyang Lyu , Wei Biao Wu

This paper investigates statistical inference for noisy matrix completion in a semi-supervised model when auxiliary covariates are available. The model consists of two parts. One part is a low-rank matrix induced by unobserved latent…

统计方法学 · 统计学 2024-03-27 Shujie Ma , Po-Yao Niu , Yichong Zhang , Yinchu Zhu

We develop a computational procedure to estimate the covariance hyperparameters for semiparametric Gaussian process regression models with additive noise. Namely, the presented method can be used to efficiently estimate the variance of the…

机器学习 · 计算机科学 2022-06-22 Siavash Ameli , Shawn C. Shadden

Training semantic segmentation models with few annotated samples has great potential in various real-world applications. For the few-shot segmentation task, the main challenge is how to accurately measure the semantic correspondence between…

计算机视觉与模式识别 · 计算机科学 2022-08-02 Zhitong Xiong , Haopeng Li , Xiao Xiang Zhu

The disconnected part of the power spectrum covariance matrix (also known as the "Gaussian" covariance) is the dominant contribution on large scales for galaxy clustering and weak lensing datasets. The presence of a complicated sky mask…

宇宙学与河外天体物理 · 物理学 2019-12-02 Carlos García-García , David Alonso , Emilio Bellini

Accurately estimating the statistical properties of noise is important in data analysis for space-based gravitational wave detectors. Noise in different time-delay interferometry channels correlates with each other. Many studies often…

天体物理仪器与方法 · 物理学 2025-06-18 Ya-Nan Li , Yi-Ming Hu , En-Kun Li

In this paper, an alternative approximation to the innovation method is introduced for the parameter estimation of diffusion processes from partial and noisy observations. This is based on a convergent approximation to the first two…

最优化与控制 · 数学 2013-12-19 J. C. Jimenez

We study the uncertainty in different two-point correlation function (2PCF) estimators in currently available galaxy surveys. This is motivated by the active subject of using the baryon acoustic oscillations (BAOs) feature in the…

宇宙学与河外天体物理 · 物理学 2011-09-08 Antoine Labatie , Jean-Luc Starck , Marc Lachièze-Rey , Pablo Arnalte-Mur