  We present an approach to the estimate of the potential of mean force along a
generic reaction coordinate based on maximum likelihood methods and
path-ensemble averages in systems driven far from equilibrium. Following
similar arguments, various free energy estimators can be recovered, all
providing comparable computational accuracy. The method, applied to the
unfolding process of the alpha-helix form of an alanine deca-peptide, gives
results in good agreement with thermodynamic integration.
