Best median values for cosmological parameters

Abstract

Our procedure to obtain best values for cosmological parameters from five recent multiparameter fits is as follows. We first study the values quoted for $r, \alpha_s, w+1 (w_0+1), w_1$ and $\Omega_k$, arriving at the conclusion that they do not differ significantly from zero, and their correlations to other parameters are insignificant. In what follows they can be therefore fixed. The neutrino mass sum $\Sigma m_{\nu}$ also does not differ significantly from zero, but since neutrinos are massive their sum must be included as a free parameter. We then compare the values obtained in five large flat-space determinations of the parameters $\Sigma m_{\nu}, \omega_b, \omega_m, h, \tau, n_s, A_s$ and $\sigma_8$. For these we compute the medians and the 17-percentile and 83-percentile errors by a described procedure.