Báo cáo khoa học: "Importance of Pronominal Anaphora resolution in Question Answering systems" pot

TEXT COLLECTION LAT FBIS TIME FT CISI MED CACM LISA FR CRANFIELD
Pronoun type
HE, SHE, THEY 38,59% 29,15% 31,20% 26,20% 15,38% 15,07% 8,59% 12,24% 13,31% 6,54%
HIS, HER, THEIR 25,84% 21,54% 35,01% 20,52% 22,96% 21,46% 15,69% 31,03% 20,70% 10,35%
IT, ITS 26,92% 39,60% 22,43% 46,68% 52,11% 57,41% 67,61% 47,86% 61,06% 79,76%
HIM, THEM 7,04% 7,08% 7,82% 4,44% 6,38% 3,96% 4,87% 6,30% 3,45% 1,60%
HIM, HER,IT(SELF), THEMSELVES 1,61% 2,63% 3,54% 2,17% 3,17% 2,10% 3,25% 2,57% 1,48% 1,75%
Pronouns in Sentences
Containing 0 pronouns 44,80% 48,09% 51,37% 64,04% 75,06% 77,84% 79,06% 83,79% 84,92% 90,95%
Containing 1 pronoun 30,40% 31,37% 29,46% 23,07% 17,17% 15,02% 17,54% 13,01% 11,64% 8,10%
Containing 2 pronouns 14,94% 12,99% 12,26% 8,54% 5,27% 4,75% 2,79% 2,56% 2,57% 0,85%
Containing +2 pronouns 9,86% 7,55% 6,90% 4,34% 2,51% 2,39% 0,60% 0,64% 0,88% 0,09%
Ratio of pronominal reference 55,20% 51,91% 48,63% 35,96% 24,94% 22,16% 20,94% 16,21% 15,08% 9,05%
Procedure SelectingAntecedent ( INPUT L: ListOfCandidates,
OUTPUT Solution: Antecedent )
Apply restrictions to L with a result of L1
Morphologic agreement
C-command constraints
Semantic consistency
Case of:
NumberOfElements (L1) = 1
Solution = TheFirstOne (L1)
NumberOfElements (L1) = 0
Exophora or cataphora
NumberOfElements (L1) > 1
Apply preferences to L1 with a result of L2
1) Candidates in the same sentence as anaphor.
2) Candidates in the previous sentence

3) Preference for proper nouns.
4) Candidates in the same position as the anaphor
with reference to the verb (before or after).
5) Candidates with the same number of parsed
constituents as the anaphora
6) Candidates that have appeared with the verb of
the anaphor more than once
7) Preference for indefinite NPs.
Case of:
NumberOfElements (L2) = 1
Solution = TheFirstOne (L2)
NumberOfElements (L2) > 1
Extract from L2 in L3 those candidates that have
been repeated most in the text
If NumberOfElements (L3) > 1
Extract from L3 in L4 those candidates that
have appeared most with the verb of the
anaphora
Solution = TheFirstOne (L4)
Else
Solution = TheFirstOne (L3)
EndIf
EndCase
EndCase
EndProcedure
Question: “Who is the village head man of Digha ?”
Answer: “
He
is the sarpanch, or village head man of
Digha, a hamlet or mud-and-straw huts 10

miles from
”
Group B Example
Anaphora resolution:
R
a
m B
a
h
adu
Question: “What did Democrats propose for low-income
families?”
Answer: “
They
also want to provide small subsidies for
low-income families in which both parents work
at outside jobs
.
”
Group C Example
Anaphora resolution:
Democrats
Baseline Anaphora solved
Answer Type Number Target included Correct answer Target included Correct answer
A 37 (39,78%) 18 (48,65%) 18 (48,65%) 18 (48,65%) 18 (48,65%)
B 25 (26,88%) 12 (48,00%) 0 (0,00%) 12 (48,00%) 12 (48,00%)
C 31 (33,33%) 9 (29,03%) 9 (29,03%) 21 (67,74%) 21 (67,74%)
A+B+C 93 (100,00%) 39 (41,94%) 27 (29,03%) 51 (54,84%) 51 (54,84%)
Baseline Anaphora solved
Answer Type Number Target included Correct answer Target included Correct answer

A 37 (39,78%) 18 (48,65%) 18 (48,65%) 18 (48,65%) 18 (48,65%)
B 20 (21,51%) 10 (50,00%) 0 (0,00%) 10 (50,00%) 10 (50,00%)
C 26 (27,96%) 9 (34,62%) 9 (34,62%) 18 (69,23%) 18 (69,23%)
A+B+C 83 (89,25%) 37 (44,58%) 27 (32,53%) 46 (55,42%) 46 (55,42%)