It has been found previously that AutoDock Vina docking performs well in the prediction of ligand binding energy for a given site provided there is a pre-calculated calibration between the Vina score (kcal/mole) and the experimental value for the binding energy for 6-10 ligands. This scheme produced results comparable to more elaborate methods, as tested in a docking challenge (www.drugdesigndata.org). For a beta-secretase enzyme, this algorithm gave results with root mean square error of 1.4 kcal/mole.