Are priors responsible for cosmology favoring additional neutrino
  species?
  It has been suggested that both recent cosmological data and the results of
flavor oscillation experiments (MiniBooNE and LSND) lend support to the
existence of low-mass sterile neutrinos. The cosmological data appear to weakly
favor additional forms of radiation in the Universe, beyond photons and three
standard neutrino families. We reconsider the cosmological evidence by making
the resulting confidence intervals on the additional effective neutrino species
as prior-independent as possible. We find that, once the prior-dependence is
removed, the latest cosmological data show no evidence for deviations from the
standard number of neutrino species.
