- Beihang
- 1.
“ 2.
- 3.
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Big Data“ 5. GoogleBaidu 6.
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- 20160923
1. 2. - - PDF document
1. 2. 3. 4. Big Data
“ 2.
Big Data“ 5. GoogleBaidu 6.
– –
–
–
– v.s.
– “retrieval performance evaluation
– Answer precise question precisely. – Partially answer question. – Suggest a source for more information. – Give background information. – Remind the user of other knowledge.
“
–
–
4
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– Batch mode
– “Interactive retrieval
– –
– “
– ““
CR CA CRa
Recall = Ra R A Ra = Precision
– Rq={d3,d5,d9,d25,d44,d56,d71,d89,d123,d23} – “
{ d123, d84, d56, d6, d8, d9, d511, d129, d187, d25, d38, d48,d250, d113,d3 }
20%...90%, 100%
(
61027254 .1033 610272547.1033861
– 11
– “
{ d123, d84, d56, d6, d8, d9, d511, d129, d187, d25, d38, d48,d250, d113,d3 }
Recall: 33.3%, 66.7%, 100% Precision: 33.3%, 25%, 20%
%
.11 .0503275.1167
1
j j j
r r r
+
≤ ≤
% %(
)
21044 .72138365821044972
– “ –
=
Nq i q i
1
NqPi(r)r
FPR: Fall-out FNR: Missing rate TNR: Specificity
Precision v.s. Accuracy ROC: Receiver Operating Curve AUC: Area Under the Curve
63 37 72 28
– 5/10
– “RR
R R Precision R
−
– APri,
– , MAP
∑
= =
× =
– “
065240-3.
0-34.
– – E
r p pr r p + = ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + = 2 1 1 2 F
( )
⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + + − = p r b b 1 1 1 E
2 2
Gain
– CG – DCG – NDCG
– /
– C=Rk/U
– novelty=Ru/(Rk+Ru)
– “
– “
– Text REtrieval Conference“ – “
– NIST(National Institute of Standards and Technology) – U.S. Department of Defense
– “ – 1992~201221
“
–
– TREC
– “ – topicèquery () – Question (QA)
–
–
)
– : NIST – : – : NIST – : NIST
– GB – – SGML (Standard Generalized Markup Language)
– – SGML
–
Title
<topic number="2" type="diagnosis"> <description> A 62 yo male presents with four days of non-productive cough and one day of fever. He is on immunosuppressive medications, including prednisone. He is admitted to the hospital, and his work-up includes bronchoscopy with bronchoalveolar lavage (BAL). BAL fluid examination reveals
</description> <summary> A 62-year-old immunosuppressed male with fever, cough and intranuclear inclusion bodies in bronchoalveolar lavage </summary> </topic>
– Set Precision/Set Recall
– P@n/Average Precision/Reciprocal Rank
– Filtering Utility
– n
recall)
–
–
– NII (National Institute of Informatics) “ – 1998 – “ –
– 2000 –