  We investigate if the observed small and nearly scale-invariant primordial
cosmic perturbation, i.e. the perturbation amplitude $P_\zeta\sim10^{-9}$ and
the spectral index $n_s \simeq 0.965$, is typical in the landscape of vacua
after imposing anthropic selections on them. We consider the situation where
the universe begins from a metastable vacuum driving a precedent inflation, a
curvature-dominated open universe is created by tunneling, and the curvature
energy is inflated away by new inflation. We argue that the initial inflaton
field value is homogeneous but typically non-zero because of the quantum
fluctuation of long wavelength modes created during the precedent inflation,
and only the universe which accidentally has a small inflaton field value is
anthropically selected. We show that this bias, together with certain
distributions of inflation model parameters that are physically well-motivated,
makes the observed small and nearly scale-invariant spectrum typical.
