Appropriate methods to combine forward and reverse free-energy perturbation averages

Different methods to combine forward and reverse free-energy perturbation averages for two systems were analyzed. The methods were examined in several applications such as the chemical potential of a high-density Lennard-Jones system and the chemical potential of a model for water. The analysis showed that the Bennet's method weighting are very effective at obtaining an accurate result for combining forward and reverse free-energy perturbation averages.