Extended Data Fig. 4: Potential factors impacting the formula annotation performance on tested metabolomics datasets.
From: BUDDY: molecular formula discovery via bottom-up MS/MS interrogation
a, The relative mass deviations of experimental precursor masses from theoretical masses for all identified metabolites. b, The number of reserved fragments (maximum: 50) after low-abundance noise ions and MS/MS isotopic peaks are removed in MS/MS preprocessing. c, The number of valid fragments that are subformula-explainable using the ground-truth molecular formulae.
