1999/12/06 by O. Lahav, S. L. Bridle, M. P. Hobson +3 · 2 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Particle physics theoretical and experimental studies #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2000.03633.x
published as Mon.Not.Roy.Astron.Soc. 315 (2000) L45 · submitted to MNRAS, 6 pages, Latex, with 3 figures embedded
arxiv created 1999/12/06 · openalex publication_date 2000/07/11 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Recently several studies have jointly analysed data from different cosmological probes with the motivation of estimating cosmological parameters. Here we generalize this procedure to allow freedom in the relative weights of various probes. This is done by including in the joint χ2 function a set of 'hyper-parameters', which are dealt with using Bayesian considerations. The resulting algorithm, which assumes uniform priors on the log of the hyper-parameters, is very simple: instead of minimizing Σχ2j (where χ2j is per data set j) we propose to minimize ΣNj1n(χ2j) (where Nj is the number of data points per data set j). We illustrate the method by estimating the Hubble constant H0 from different sets of recent cosmic microwave background (CMB) experiments (including Saskatoon Phyton V, MSAM1, TOCO and Boomerang). The approach can be generalized for combinations of cosmic probes, and for other priors on the hyper-parameters.