Fig. 4
From: A European proposal for quality control and quality assurance of tandem mass spectral libraries
Overview on the average match probability (amp) distribution obtained from matching 352 positive controls representing 87 compounds part of the UFZ library to the WRTMD. An amp-threshold of 5.0 was used to distinguish between positive and negative matches. The overall sensitivity was 89.7%. For 70 compounds, all test spectra led to positive matches with amp>5.0. For sixteen compounds at least one test spectrum retrieved an amp-value below the specified threshold of 5.0 indicating insufficient similarity between test and reference spectra