  The cosmological principle is fundamental to the standard cosmological model.
It assumes that the Universe is homogeneous and isotropic on very large scales.
As the basic assumption, it must stand the test of various observations. In
this work, using the region fitting (RF) method, we mapped the all-sky
distribution of cosmological parameters ($\Omega_{m}$ and $H_{0}$) and find
that the distribution significantly deviates from isotropy. A local matter
underdensity region exists toward (${308.4^{\circ}}$$_{-48.7}^{+47.6}$,
${-18.2^{\circ}}$$_{-28.8}^{+21.1}$) as well as a preferred direction of the
cosmic anisotropy (${313.4^{\circ}}$$_{-18.2}^{+19.6}$,
${-16.8^{\circ}}$$_{-10.7}^{+11.1}$) in galactic coordinates. Similar
directions may imply that local matter density might be responsible for the
anisotropy of the accelerated expansion of the Universe. Results of statistical
isotropy analyses including Isotropy and Isotropy with real-data positions (RP)
show high confidence levels. For the local matter underdensity, the statistical
significances are 2.78$\sigma$ (isotropy) and 2.34$\sigma$ (isotropy RP). For
the cosmic anisotropy, the statistical significances are 3.96$\sigma$
(isotropy) and 3.15$\sigma$ (isotropy RP). The comparison of these two kinds of
statistical isotropy analyses suggests that inhomogeneous spatial distribution
of real sample can increase the deviation from isotropy. The similar results
and findings are also found from reanalyses of the low-redshift sample (lp+)
and the lower screening angle ($\theta_\mathrm{max}$ = 60$^{\circ}$), but with
a slight decrease in statistical significance. Overall, our results provide
clear indications for a possible cosmic anisotropy. This possibility must be
taken seriously. Further testing is needed to better understand this signal.
