<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="83">
<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>
;ults - Daihousie University
Summary Statistics
Run Number DalTx2-category B, manual 1 1
Num of Queries 50
Total number of documents over all queries
0.8
Retrieved: 11987
Relevant: 2064
Rel[OCRerr]ret: 881 0.6
call Level_Averages
[OCRerr]ecall Precision
0.00 0.2984
0.10 0.2029
0.20 0.1661
0.30 0.1415
0.40 0.1056
0.50 0.0714
0.60 0.0691
0.10 0.0488
0.80 0.0111
0.90 0.0002
1.00 0.0002
3ge precision over all
[OCRerr]nt docs
nterpolated 0.0893 1
Level Averages
t Recall
0 0.1023
.0 0.1559
[OCRerr] 0.2034
0 0.2353
[OCRerr]o 0.2516
)0 0.2135
[OCRerr]0 0.2181
LO 0.2854
)0 0.2890
30 0.3151
)0 0.3305
Document Level Averages
Precision
At 5 docs 0.1320
At 10 docs 0.1280
At 15 docs 0.1301
At 20 docs 0.1310
At 30 docs 0.1213
At 100 docs 0.1040
At 200 docs 0.0645
At 500 docs 0.0334
At 1000 docs 0.0114
Precision
0.4
0.2
0
[OCRerr]L Precision (precision after R
docs retrieved (where R is
the number of relevant docu-
ments))
Fxact 0.1199
NORMAL DEVIATE - Fallout-Recall Recall
Ol a.02 0.16 ( 5 0.84 0.98 0. 9[OCRerr]999 0.4
:1:1
7' 0.98
2
1 0.84
0 0.5
-1 0.16
-2 0.02
-3 -7" 0.001
I I _______________
3 -2 -1 0 1 2 3
Recall-Precision Curve
I I I
1
0 0.2 0.4 0.6 0.8
Recall
Fallout-Recall Curve
1 I I
0.8
0.6
0.2
I I I
0
0 0.05 0.15
0.1
Fallout x 100
0.2
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</PAGE>
</DOC>