  We have made a likelihood statistical analysis of the angular correlations in
the {\it COBE}-DMR two-year sky maps by Monte Carlo simulation of the
temperature fluctuations. We assume an open universe and consider as primordial
power spectrum the Harrison-Zeldovich one, $P(k)=Ak$. We find that the flatness
of the universe is not implied by the data. The quadrupole normalization
amplitude, $Q_{rms-PS}$, is related to the density parameter, $\Omega$, by
$Q_{rms-PS} = 10.67 + 55.81 \Omega - 128.59 \Omega^2 + 81.26 \Omega^3\ \mu$K.
We have determined the p.d.f. of $\Omega$ due to cosmic plus sampling (i.e.
$20^\circ$ galactic cut) variance which generically shows a bimodal shape. The
uncertainty as given by the r.m.s. is $\approx 0.35$, therefore to better
constrain $\Omega$ experiments sensitive to higher multipoles ($l>20$) should
be considered.
