1. Question Classification
(Reading Report & Current Progress)
Qingxia Liu

2. Question Classification (QC)
What is QC?
categorize questions into different semantic classes that impose constraints on potential answers, so that they can be utilized in later stages of the question answering process.
Related Works
[LD’02] Xin Li, Dan Roth: Learning Question Classifiers. COLING 2002
[LD’06] Xin Li, Dan Roth:Learning question classifiers: the role of semantic information. Natural Language Engineering 12(3): (2006)
[TL’16]Harish Tayyar Madabushi, Mark Lee: High Accuracy Rule-based Question Classification using Question Syntax and Semantics. COLING 2016:

3. Learning QC [LD’02] Contributions a layered semantic hierarchy
a hierarchical classifier
an annotated question set

4. examples (coarse:fine class )
ABBR:exp
What is the full form of .com ?
What does S.O.S. stand for ?
DESC:manner
How did serfdom develop in and then leave Russia ?
DESC:desc
What is the daily requirement of folic acid for an expectant mother ?
ENTY:animal
What fowl grabs the spotlight after the Chinese Year of the Monkey
HUM:ind
Who was the inventor of silly putty ?
LOC:state
Which two states enclose Chesapeake Bay ?
NUM:date
When was the battle of the Somme fought ?
NUM:volsize
What is the size of the largest akita ?

5. Learning QC [LD’02]

6. Learning QC [LD’02] Syntactic Features Semantic Features words POS
chunks
non-overlapping phrases in a sentence
head chunks
e.g. the first noun chunk and the first verb chunk after the question word in a sentence
Semantic Features
SemWN
wordNet sense and direct hypernym and hyponym
SemCSR
class-specific related words
SemSWL
distributional similarity based categories

7. Rule-based QC [TL’16]
“Name of actress from England in the movie ‘The Titanic’ is what?”
Rewrite: “What is the name of the actress from England in the movie ‘The Titanic’?”
SynMap: ...
head-word: actress; wh-word: What; aux-verb: is
classification by rule: occupation.n.01 + what -> hum:ind

8. Rule-based QC [TL’16] Syntactic Map: wh-word
NP in the WHNP sub-tree and its internal phrase structure
Auxiliary Verb (AVP)
NP and its internal phrase structure
the Main Verb (MVP)

9. Rule-based QC [TL’16]

10. Current Progress Goal Last week This week
classify questions according to patterns which indicates their potential solving strategy (e.g.structured query template)
Last week
word function based sentence pattern
E, V, X, Struct
This week
word function + layered statement tree (F)

11. Layered Statement Tree
Each non-preterminal layer represents a statement
Generated by contraction of syntactic tree

12. LST + WF Split sentence into statements using LST
Convert each statement into pattern using WF
Who V the X for F F1

13. Preliminary Result Analyzing the top-layer: 1. Free917 (314/458/917)
Pattern
num
Example
what be F
146
what is the address of the apple, inc. headquarters
what F 59
what olympics has egypt participated in
who V E 42
who designed the iphone
how many F 41
how many companies are traded by the nyse
who be F 37
who are some practitioners of judo
when be E V 31
when was wells fargo founded
F be there 16
how many first generation particles are there
how many X do E have 14
how many floors does the white house have
what X do E X 13
what conferences does google sponsor
when be X V
when was savealot founded
where be E V 12
where was jerry seinfeld born
F be E 9
what issue of sandman is a dream of a thousand cats
how many X V in E
how many teams participate in the uefa
how X be E
how tall is westminster abbey
how many X V E 7
how many people survived the sinking of the titanic

14. Preliminary Result Analyzing the top-layer: 2. QALD (303/441/679)
Pattern
num
Example
give I F 57
Give me the websites of companies with more than employees.
who be F 51
Who was the wife of President Lincoln?
what be F
What is the official website of Tom Hanks?
X F 16
List all episodes of the first season of the HBO television series "The Sopranos"!
which F 14
Which states of Germany are governed by the Social Democratic Party?
give I all X 10
Give me all school types.
who V E
Who created Goofy?
who V F 9
Who developed the video game World of Warcraft?
which X have X than X 8
Which caves have more than 3 entrances?
which X have the X
Which country has the most official languages?
how many X do E have
How many employees does IBM have?
who V X 7
Who created English Wikipedia?
which X do E V 6
Which river does the Brooklyn Bridge cross?
which X V E
Which states border Utah?
give I all E
Give me all presidents of the United States.

15. Example
548. Who of those resting in Westminster Abbey wrote a book set in London and Paris?
Statements
[F1, write, F2, ?]
F1: [who, of, F3], F2:[a book, set, in, london and paris]
F3: [those rest, in, <e>]
Top layer: [F, write, F, ?]
Target statemet: who of F write F
453. Gaborone is the capital of which country member of the African Union?
[<e>, be, F1, ?]
F1: [the capital, of, F1]
F2: [which country member, of, the african union]

16. Next Alignment-based Clustering alignment with cost cost(F -> E)=0
Question
Confirmation
be E a X
do E V X
Entity
Give I all X
What X V E
Time
When be E V
Location
Where be F
Number
How many X do F have
How X be E
Description
How do E V
Why do E V X
Alignment-based Clustering
alignment with cost
cost(F -> E)=0
cost(which X->which)=0.5

17. Thank you ~