  Our purpose is to find which is the most reliable one among various oxygen
abundance determination methods. We will test the validity of several different
oxygen abundance determination methods using methods of modern statistics.
These methods include Bayesian analysis and information scoring. We will
analyze a sample of $\sim$6000 $\hii$ galaxies from the Sloan Digital Sky
Survey (SDSS) spectroscopic observations data release four. All methods that we
used drew the same conclusion that the $T_e$ method is a more reliable oxygen
abundance determination methods than the Bayesian metallcity method under the
existing telescope ability. The ratios of the likelihoods between the different
kinds of methods tell us that the $T_e$, $P$, and $O3N2$ methods are consistent
with each other because the $P$ and $O3N2$ method are calibrated by
$T_e$-method. The Bayesian and $R_{23}$ method are consistent with each other
because both are calibrated by a galaxy model. In either case, the $N2$ method
is an {\it unreliable} method.
