1 research outputs found
Limitations of Bayesian Evidence Applied to Cosmology
There has been increasing interest by cosmologists in applying Bayesian
techniques, such as Bayesian Evidence, for model selection. A typical example
is in assessing whether observational data favour a cosmological constant over
evolving dark energy. In this paper, the example of dark energy is used to
illustrate limitations in the application of Bayesian Evidence associated with
subjective judgements concerning the choice of model and priors. An analysis of
recent cosmological data shows a statistically insignificant preference for a
cosmological constant over simple dynamical models of dark energy. It is argued
that for nested problems, as considered here, Bayesian parameter estimation can
be more informative than computing Bayesian Evidence for poorly motivated
physical models.Comment: 8 pages 4 figures MNRAS accepted. Substantially revised and extende