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We compile a large sample of 120 Seyfert 2 galaxies (Sy2s) which contains 49hidden broad-line region (HBLR) Sy2s and 71 non-HBLR Sy2s. From the differencein the power sources between two groups, we test if HBLR Sy2s are dominated byactive galactic nuclei (AGNs), and if non-HBLR Sy2s are dominated bystarbursts. We show that: (1) HBLR Sy2s have larger accretion rates thannon-HBLR Sy2s; (2) HBLR Sy2s have larger \Nev $\lambda 14.32$/\Neii $\lambda12.81$ and \oiv $\lambda 25.89$/\Neii $\lambda 12.81$ line ratios than non-HBLRSy2s; (3) HBLR Sy2s have smaller $IRAS$ $f_{60}/f_{25}$ flux ratio which showsthe relative strength of the host galaxy and nuclear emission than non-HBLRSy2s. So we suggest that HBLR Sy2s and non-HBLR Sy2s are AGN-dominated andstarburst-dominated, respectively. In addition, non-HBLR Sy2s can be classifiedinto the luminous ($L_{\rm [O III]}>10^{41} \rm ergs s^{-1}$) and less luminous($L_{\rm [O III]}<10^{41} \rm ergs s^{-1}$) samples, when considering onlytheir obscuration. We suggest that: (1) the invisibility of polarized broadlines (PBLs) in the luminous non-HBLR Sy2s depends on the obscuration; (2) theinvisibility of PBLs in the less luminous non-HBLR Sy2s depends on the very lowEddington ratio rather than the obscuration.

The Different Nature in Seyfert 2 Galaxies With and Without Hidden Broad-Line Regions