  We numerically analyze the transmission through a thin disordered wire of
finite length attached to perfect leads, by making use of banded random
Hamiltonian matrices. We compare the Landauer and the Thouless conductances,
and find that they are proportional to each other in the diffusive regime,
while in the localized regime the Landauer conductance is approximately
proportional to the square of the Thouless one. Fluctuations of the Landauer
conductance were also numerically computed; they are shown to slowly approach
the theoretically predicted value.
