Statistical evaluation of the observational information on Omega(m) and Omega(Lambda)

We undertake a critical evaluation of recent observational information on O mega (m) and Omega (Lambda) in order to identify possible sources of system atic errors and effects of simplified statistical analyses. We combine obse rvations for which the results have been published in the form of likelihoo d contours in the Omega (m), Omega (Lambda) plane. We approximate the conto urs by fifth order polynomials, and we then use the maximum likelihood meth od to obtain joint likelihood contours for the combined data. In the choice of statistical merits we aim at minimum loss of information rather than at minimum variance. We find that Omega (0) = Omega (m) + Omega (Lambda) = 0. 99 +/- 0.04 +/- 0.03, where the first error is mainly statistical and the s econd error is systematical. In a at Universe we find Omega (flat)(m) = 0.3 1 +/- 0.04 +/- 0.04.