  The link between the scaling function extracted from the analysis of (e,e')
cross sections and the spectral function/momentum distribution in nuclei is
revisited. Several descriptions of the spectral function based on the
independent particle model are employed, together with the inclusion of nucleon
correlations, and effects of the energy dependence arising from the width of
the hole states are investigated. Although some of these approaches provide
rough overall agreement with data, they are not found to be capable of
reproducing one of the distinctive features of the experimental scaling
function, namely its asymmetry. However, the addition of final-state
interactions, incorporated in the present study using either relativistic mean
field theory or via a complex optical potential, does lead to asymmetric
scaling functions in accordance with data. The present analysis seems to
indicate that final-state interactions constitute an essential ingredient and
are required to provide a proper description of the experimental scaling
function.
