<DOC> <DOCNO> SP500215 </DOCNO> <TITLE> NIST Special Publication 500-215: The Second Text REtrieval Conference (TREC-2) </TITLE> <SUBTITLE> Appendix A: TREC-2 Results </SUBTITLE> <TYPE> Appendix </TYPE> <PAGE CHAPTER="A" NUMBER="80"> <AUTHOR1> </AUTHOR1> <PUBLISHER> National Institute of Standards and Technology </PUBLISHER> <EDITOR1> D. K. Harman </EDITOR1> <COPYRIGHT MTH="March" DAY="" YEAR="1994" BY="National Institute of Standards and Technology"> </COPYRIGHT> <BODY> results - VPI & SU Summary Statistics J Run Number VTcms2-ful I, manual 1 Recall-Precision Curve Num of Queries 50 J 1 Total number of documents over all queries 1 Retrieved: 50000 0.8 Relevant: 19489 Reljet: 5898 Recall Level_Averages Recall Precision 0.00 0.7524 0.10 0.5342 0.20 0.4510 0.30 0.3828 0.40 0.3063 0.50 0.2539 0.60 0.1817 0.70 0.1270 0.80 0.0809 0.90 0.0496 1.00 0.0060 rage precision over all [OCRerr]ant docs -interpolated 0.2681 J it Level Averages Lit Recall 00 0.3015 20 0.3795 40 0.4320 60 0.4660 BO 0.4986 DO 0.5250 20 0.5421 40 0.5577 60 0.5745 BO 0.5916 DO 0.6021 Document Level Averages Precision At 5 docs 0.6080 At 10 docs 0.5760 At 15 docs 0.5387 At 20 docs 0.5160 At 30 docs 0.4913 At 100 docs 0.3806 At 200 docs 0.2953 At 500 docs 0.1882 At 1000 docs 0.1180 R-Precision (precision after R docs retrieved (where R is the number of relevant docu- ments)) 0.6 Precision 0.4 0.2 0 1 0.8 Exact 0.3143 0.6 NORMAL DEVIATE - Fallout-Recall Ol 0[OCRerr]02 0.84 0.98 0 0.4 0.2 - 2 0.98 Recall 0 0.2 0.4 0.6 0.8 Recall Fallout-Recall Curve I I I I 1 0.84 0 0.5 0 0 0.05 0.1 0.15 0.2 -1 0.16 Fallout x 100 -2 0.02 -3 0.001 -3 -2 -1 1 2 3 </BODY> </PAGE> </DOC>