Table : Computed and experimental relative mean energy differences between pairs of peptides. Relative binding enthalpies (∆∆H), binding site energy differences (∆u B ), relative ligand-protein interaction energies (∆∆u inter ), and relative changes in ligand internal energy on binding (∆∆u L ) for each ligand pair, computed with the combined (concatenated) parallel runs for each system (Runs A and B); results in kcal/mol. The relative difference in all remaining terms is also reported, as ∆∆u other ; see main text. The standard errors of the mean (SEM) (σ) are propagated from those estimated using the statistical inefficiency applied to combined runs. The experimental errors are taken from , which are propagated from the errors in ligand concentration.