Estimating cosmological parameter covariance
نویسندگان
چکیده
منابع مشابه
The covariance of cosmic shear correlation functions and cosmological parameter estimates using redshift information
Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements Cosmic Microwave Background studies, by breaking degeneracies and providing a cross-check. Furthermore, upcoming cosmic shear surveys with photometric redshift information will ena...
متن کاملEstimating Model Parameters with Ensemble-Based Data Assimilation: Parameter Covariance Treatment
In this work, various methods for the estimation of the parameter uncertainty and the covariance between the parameters and the state variables are investigated using the local ensemble transform Kalman filter (LETKF). Two methods are compared for the estimation of the covariances between the state variables and the parameters: one using a single ensemble for the simultaneous estimation of mode...
متن کاملTesting Cosmological Models and Understanding Cosmological Parameter Determinations with Metaparameters
Cosmological parameters affect observables in physically distinct ways. For example, the baryon density, ωb, affects the ionization history and also the pressure of the pre-recombination fluid. To investigate the relative importance of different physical effects to the determination of ωb, and to test the cosmological model, we artificially split ωb into two ‘metaparameters’: ωbe which controls...
متن کاملEstimating the covariance function with functional data.
This paper describes a two-step procedure for estimating the covariance function and its eigenvalues and eigenfunctions in situations where the data are curves or functions. The first step produces initial estimates of eigenfunctions using a standard principal components analysis. At the second step, these initial estimates are smoothed via local polynomial fitting, with the bandwidth in the ke...
متن کاملEstimating the Covariance of Random Matrices
We extend to the matrix setting a recent result of Srivastava-Vershynin [21] about estimating the covariance matrix of a random vector. The result can be interpreted as a quantified version of the law of large numbers for positive semi-definite matrices which verify some regularity assumption. Beside giving examples, we discuss the notion of log-concave matrices and give estimates on the smalle...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2014
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/stu996