. Author manuscript; available in PMC: 2010 Jul 8.

Published in final edited form as: Proteomics. 2009 Mar;9(5):1220–1229. doi: 10.1002/pmic.200800473

Table 2.

The e-value threshold at which 50% peptide FDR is achieved in the three search engines

Experiment identifier	Mascot 50% FDR	Omssa 50% FDR	X!Tandem 50% FDR

PA77	4	200	0.3
PA93	4	60	0.125
PA138	0.6	35	0.175
PA146	5	80	0.125
PA157	0.9	35	0.07
PA158	3	500	1.5
PA160	4	200	1.5
PA162	0.8	60	0.125
PA165	4	500	1
PA166	2	100	1.5
PA167	0.9	25	0.4

Mean	2.65	163	0.62