test 1:
number of matches PI+:				1053
number of matches SEQ+:				959
number of matches SEQ+P+:			801
number of matches SEQ-PI+:			252
number of matches by inspection among SEQ-PI+:	171
sensitivity = (801+171)/(959+171) = 86.0%
error rate = (1053-801-171)/1053 = 7.7%

test 2:
number of matches PI+:				1150
number of matches SEQ+:				1073
number of matches SEQ+P+:			905
number of matches SEQ-PI+:			245
number of matches by inspection among SEQ-PI+:	185
sensitivity = (905+185)/(1073+185) = 86.6%
error rate = (1150-905-185)/1150 = 5.2%

test 3:
number of matches PI+:				994
number of matches SEQ+:				870
number of matches SEQ+P+:			763
number of matches SEQ-PI+:			231
number of matches by inspection among SEQ-PI+:	164
correct rate: (763+164)/(870+164) = 89.7% 
error   rate: (994-763-164)/994 = 6.7%

average correct rate = ( 86.0% + 86.6% + 89.7% ) / 3 = 87.4%
average error rate = ( 86.0% + 86.6% + 89.7% ) / 3 = 6.5%