Comparison of four commercially available predictors. a) Results of the evaluation of 4 1H NMR predictors using the new methodology. Each point in the plot corresponds to the fraction of correct matches within the n highest-ranking hits of a query of 1000 simulated 1H spectra to the database of the corresponding experimental spectra. For example, using predictor A, around 75% of the correct matches are found within the 4 highest ranked hits. Higher curves then represent better performance. Overall MRRs obtained for each predictor are specified in the legend. b) Results of the evaluation using direct comparison of predicted and observed chemical shifts. Each point in the plot corresponds to the fraction of predicted chemical shifts that fall within the specified deviation from the observed shift. For example, using predictor A, around 75% of the predicted peaks fall within 0.15 ppm of the observed peaks. Higher curves then represent better performance.