The density function for the group with 5 "yellow cards" was scaled so that the areas within the range from 0 to 30 seconds were identical for groups with 0 and 5 "yellow cards". The number of incorrectly predicted retention times was estimated by subtracting the density for the group with 0 "yellow cards" from the scaled density function and normalizing the result by the total number of retention times in the group with 5 "yellow cards". This estimate revealed 303 ± 11 (standard deviation) inaccurately predicted compounds and 1231 ± 11 compounds with potentially erroneous experimental retention times. These two independent estimates give similar results and align closely with the intersection of three runs with varying train-prediction splits. It makes us believe that the number of potentially erroneous retention times in the METLIN SMRT database is about 1200 (or 1.5%), while the group with 5 "yellow cards" includes about 1500 retention times.