The advantage of Diffusion Monte Carlo with respect to usual
Variational Monte Carlo methods is that it provides the possibility
to calculate pure estimators, which have no bias due to the choice
of the trial wave function. This is true for such important
quantities as the energy, radial distribution function and
superfluid density. For other quantities such as the one body
density matrix the DMC method provides mixed estimator which, used
in correction with outputs of VMC calculations, allows one to
reduce the bias of the trial wavefunction.
Subsections