English

Reply to: Overconfidence in Bayesian analyses of galaxy rotation curves

Astrophysics of Galaxies 2020-02-11 v1 Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology

Abstract

Cameron {\it et al.}~2019 (hereafter C19) recommends a more cautious and rigorous approach to statistical analysis in astronomy. We welcome this particular side of their communication as it helps stimulating the effort towards the adoption of better statistical methods in galaxy rotation curves, an effort to which we contributed with Rodrigues {\it et al.}~2018 (hereafter R18). Indeed, R18 was the first work that, in order to conclude on the universality of the acceleration scale a0a_0, studied the posterior distributions on a0a_0 of a large set of galaxies. As C19 agrees, the credible intervals were found within the Bayesian framework, that is, the marginalized posteriors on a0a_0 were found using Bayes' theorem to update the priors in light of the observational data; this process was done without introducing any approximation. Considering R18, C19 also remarks that: i) better methods to select the nuisance parameters and the corresponding priors could be used; ii) a quality cut based on χ2\chi^2 values should not be used, and iii) the compatibility of the posteriors should be assessed in a more robust way. In the following, after first clarifying the context of our work, we address these criticisms.

Keywords

Cite

@article{arxiv.2002.01970,
  title  = {Reply to: Overconfidence in Bayesian analyses of galaxy rotation curves},
  author = {Davi C. Rodrigues and Valerio Marra and Antonino Del Popolo and Zahra Davari},
  journal= {arXiv preprint arXiv:2002.01970},
  year   = {2020}
}

Comments

4 pages. The published version (in the Matters Arising section) can be freely accessed through https://rdcu.be/b01KI