1. Pramit Roy
IIT Delhi, August 2012

2. Community Question Answering (CQA)
“Just because Google exists does not mean you should stop asking things”, A. Totsis, TechCrunch, 2010
Home > All Categories > Arts & Humanities > Philosophy

3. • Largest Community driven question/answer site with more than 1B
answers ( http://bit.ly/am1LwL )
• 4th most popular property on yahoo network
• Average Dynamics: 3.5 answers/question, 11 minutes to first answer
• Community Moderated, no editorial control
• Supports 12 languages
• Model:
– Content-driven (different from Quora , which is social-driven)
– Subjective quality model (different from WikiAnswers or
StackOverflow)
• By default broadcast questions to *all* potential users, not to a
group of specific focus
• Asker picks best answer (subjectivity rules): “Quality in the eye of
the asker” even if the community disagrees

4. • User Interest Analysis
– Seekers
– Knowledge Experts
• Sentiment Analysis

10. • Problem: About 15% of incoming questions are
unanswered
• Key observation: Certain questions are
recurrent and prevalent
– What are the symptoms of cervical cancer?
– How much weight Should I lose?
– How do you train your cat to use the litter box?
– What is a black hole?
• Possible Solution: use past answered
questions to automatically answer new
questions.

11. Title: • Non-informative, ambiguous title
How often should i jump?
• Complex information need
Body:
I have a 6yo cob, and we've started • Detailed and personal
jumping, he's done it before, we're only
jumping around 1-1,8 foot. He isn't fat
and he's quite fit. I jumped him on • Multiple questions posed in one
Friday, but did just 3 small jumps, i did
flatwork on Saturday, and jumped him 3
times today then hacked out, tomorrow, • Grammatical errors, slang
should i just flatwork him or would he be
ok to jump a few small singles? Like 3? I
won't ride him again until • Non factual, rather opinion and
Wednesday/Thursday to give him a recommendation is expected
break, what do you think? He is fine
doing what he has done, he doesn't get
sweaty much or tired, i myself am not • Extensive variability among
ready to go any higher and would like to
just do maybe 1 or 2 jumps? Is he ok to questions: in language style,
jump tomorrow? If not when next? Thank cultural aspects, degree of detail
you for the help! I appreciate it all! :) xx

14. • Users want to answer new questions
– No social information on such questions (item cold-start)
– This known scenario in recommendation systems is our typical case
• Many users are new
– Hardly any answering history (user cold-start)
– The majority of registered users
• Current solution: show most recent questions in the
category
• Goal: a question recommendation model that fits all
user types
– Active users,
– new users,
– surfers

15. • Recommender system approach, (like for movie
recommendation but in a much larger and very sparse
space)
• Learn from past interactions with users and push
relevant open questions
I want to answer, who has a question? Yahoo! Answers Recommender System ”
- G. Dror, Y. Koren, Y. Maarek and I. Szpektor, KDD’2011, San-Diego, CA

17. • Why do people ask questions on Answers?
– Users more likely to register with Y!A to ask things
they can‘t ask elsewhere (“conversational”,
”personal”, “opinion based”)
– When you can’t find what you are looking for by
search
• Different (demographic) groups use it differently
– Women ask more conversational questions
– Older people ask more informational questions
– Celebrities or professionals ask question to spread
awareness, get survey results etc

18. Credits:
Giovanni Gardelli, Ingmar Weber, Antti Ukkonen, B. Barla Cambazoglu – Y! Research Barcelona
Onur Kucuktunc, The Ohio State University, US
Hakan Ferhatosmanoglu, Bilkent University, Turkey

19. • Relating answers activity to activities around
the world.
– Huge drop in science & math category in mid-
December every year. This category is heavily used
for homework help -- effect of Christmas break?
• Android/iOS apps.
• ~ 35 small and big hacks during the 2011 Y!
hack day event @ blr.

20. • Person Genome – Everyone has a set of
interests. Good contributors in Answers
usually ask or answer most seriously in
certain specific topics, categories.
answers.yahoo.com/activity/qa?show=c8BPMeHBaa&link=question

22. • Create granular profile of users
– is_a_ps3_power_user, _is_hair_style_conscious etc
• Create a graph of profiles
– Graph of related users
Group of users with related interest
• Create question profile and match with user
profile
Recommend question for users

23. • We always have some song we want lyrics for.
– How can you ask that in Answers?
– Post a link to some streaming URL or YouTube video
– Replier will have to go to that page and come back
for answering
Embed the image and video directly in Answers
page for direct preview
Add gallery of images to support where asker can
create poll (about which shoe to buy, which hair
style etc.)

24. Answers API
•developer.yahoo.com/answers/
•Provides capabilities of searching and reading
questions and answers

26. • Yahoo Research Labs – Haifa, Israel.
Gideon Dror, Yehuda Koren, Yoelle Maarek, Dan Pelleg, Idan Szpektor, Oleg Rokhlenko
• Yahoo! Research Labs, Barcelona
Giovanni Gardelli, Ingmar Weber, Antti Ukkonen, B. Barla Cambazoglu

27. Questions for Answers?