  Studies of one-body density matrices (ODM) are performed in various
correlation methods, such as the Jastrow method, the correlated basis function
method, the Green's function method and the generator coordinate method aiming
to extract the absolute spectroscopic factors and overlap functions (OF) for
one-nucleon removal reactions from the ODM of the target nucleus. The advantage
of this method is that it avoids the complicated task of calculating the total
nuclear spectral function. The procedure for extracting bound-state OF's has
been applied to make calculations of the cross sections of the
$(e,e^{\prime}p)$ reaction on the closed-shell nuclei $^{16}$O and $^{40}$Ca as
well as on the open-shell nucleus $^{32}$S consistently (using the same OF's)
with the cross sections of $(p,d)$ and $(\gamma,p)$ reactions on the same
nuclei. The analyses of the reaction cross sections and the spectroscopic
factors and the comparison with the experimental data show the particular
importance of these OF's, since they contain effects of nucleon correlations
(short-range and/or long-range) which are accounted for to different extent in
the theoretical methods considered.
