QUESTION AND ANSWERING

Overview

What is Question Answering? Why use it? How does it work? Problems Examples Future

What is it?

Definition of Question Answering Examples

AskJeeves is probably most well known example

AnswerBus is an open-domain question answering system

Ionaut, EasyAsk, AnswerLogic, AnswerFriend, Start, LCC, Quasm, Mulder, Webclopedia, etc.

Why use it?

From AskJeeves “Search engines do not speak your language. They make you speak their language; a language that's strange, confusing, and includes words that no one is entirely sure of their meaning.”

QA engines attempt to let you ask your question the way you'd normally ask it .

Inexperienced users Document=Answer?

How does it work?

Natural Language Processing Semantic Processing Syntactic Processing Parsing

Knowledge Base Answer Processing

Natural Language Processing (NLP) Engines have unique processes

START-Natural Language System Parsing Natural Language Annotation Processing Component

QA System Output

AnswerBus Sentences

AskJeeves Documents

IONAUT Passages

LCC Sentences

Mulder Extracted answers

QuASM Document blocks

START Mixture

Webclopedia Sentences

Answer Processing

AskJeeves

Has own knowledge base and uses partners to answer questions

Catalogues previous questions Answer processing engine

Question template response

AnswerBus

Problems

How and Why questions What questions

What happened? What did we do?

Answer Quality Correct?? Answer Presentation

Correct? (From Webclopedia) Question: Where do lobsters like to live?

Answer: on a Canadian airline Question: Where do hyenas live?

Answer: in Saudi ArabiaAnswer: in the back of pick-up trucks

Question: Where are zebras most likely found?Answer: near dumpsAnswer: in the dictionary

Question: Why can't ostriches fly?Answer: Because of American economic sanctions Collected by Ulf Hermjakob --November 29, 2001

(TREC) -- Text Retrieval Conference Yearly information retrieval competition Began in 1992: QA in 1999 In order to encourage research into systems

that return answers rather than document lists.

Q’s are open domain, closed class A’s are less than 50 chars and entities or

noun phrases

(TREC) -- Text Retrieval Conference 500 Questions in 2001

Some answers = nil; large difficulty Lots of definition questions

QA list tasks Name 4 cities that have a “Shubert” theater.

QA context tasks How many species of spiders are there? How many are poisonous to humans? What percentage of spider bites in the US are fatal?

Example Questions and Results What river in the US is known as the Big

Muddy?

AskJeeves AnswerBus Google

Example Questions and Results What person’s head is on a dime?

AskJeeves AnswerBus AltaVista

Example Questions and Results Show some paintings by Claude Monet

START

Looking Ahead

User Demand Enormous Interest in Problem Successes

Conclusion

Question and Answering and Search Engines Why its used Future

Moore’s Law for QA???

Sources

AskMSR: Question Answering Using the Worldwide Web Michele Banko, Eric Brill, Susan Dumais, Jimmy Lin http://www.ai.mit.edu/people/jimmylin/publications/Banko-et

al-AAAI02.pdf

In Proceedings of 2002 AAAI SYMPOSIUM on Mining Answers from Text and Knowledge Bases, March 2002 

Web Question Answering: Is More Always Better? Susan Dumais, Michele Banko, Eric Brill, Jimmy Lin,

Andrew Ng http://research.microsoft.com/~sdumais

/SIGIR2002-QA-Submit-Conf.pdf

Sources AnswerBus 

www.answerbus.com http://misshoover.si.umich.edu/~zzheng/qa-new/ http://www2002.org/CDROM/poster/203/

AskJeeves http://www.ask.co.uk/docs/about/what_is.asp

Webclopedia http://trec.nist.gov/pubs/trec9/papers/webclopedia.pdf http://www.isi.edu/natural-language/projects/webclopedia/

Start http://www.ai.mit.edu/projects/infolab/ailab.html

 Text Retrieval Conference http://trec.nist.gov/presentations/TREC10/qa/