Fig. 4
From: rMSIfragment: improving MALDI-MSI lipidomics through automated in-source fragment annotation
Performance estimation of the ranking scores proposed using a target-decoy validation approach. The decoy database is composed of adducts and fragmentation pathways highly unlikely to be found in the lipid classes considered. Lipid occurrences (LO): number of times a given lipid is found (including parental adducts and in-source fragments); Spatial correlation (C): The weighted mean Pearson’s correlation of all m/z features annotated as the same lipid. Final ranking score (S): LO * C. A ROC curve and B FDR estimation for the negative polarity datasets (G9-G15) C ROC curve and D FDR estimation for the positive polarity datasets (G1-G8)