Question Classification (Reading Report & Current Progress) Qingxia Liu

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): 229-249 (2006) [TL’16]Harish Tayyar Madabushi, Mark Lee: High Accuracy Rule-based Question Classification using Question Syntax and Semantics. COLING 2016: 1220-1230

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

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 ?

Learning QC [LD’02]

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

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

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)

Rule-based QC [TL’16]

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)

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

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

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

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 500000 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.

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]

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

Thank you ~