  The statistical method used in the analyses of measurements of neutrino
oscillation mixing angle $\theta_{13}$ by the Daya Bay Collaboration is based
on variational minimization of a $\chi^2$ function defined in terms of
quantities of interest and pull factors which are introduced to deal with
effects of systematic uncertainties. For both experiments, the number of
parameters that need to be determined is great than the number of available
data points (20 vs 6 for the Daya Bay and 12 vs 2 for the RENO). While the
results for the mixing angle and the normalization factor were reported,
results for the other parameters (pull factors) were omitted in their
publications. There exist multiple sets of parameters from the minimization of
the $\chi^2$ function. We investigate the sensitivity of the extracted mixing
angle on this non-uniqueness of minimization results for the Daya Bay data
using two methods of minimization. We report results for all parameters,
including those of physics interest and pull factors. The obtained results for
the mixing angle and the normalization factor are in agreement with those
reported by the Daya Bay Collaboration. Furthermore, we present plots of
confidence level contours in the space of the mixing angle and normalization
factor. We also present results from fittings using a reduced $\chi^2$ function
with fewer parameters than the one employed by the Daya Bay Collaboration.
