IR, IE and QA over Social Media

1
IR, IE and QA over Social Media

• Social media (blogs, community QA, news
  aggregators)
• Complementary to traditional news sources
  (Rathergate)
• Grow faster than traditional web content, gap
  widening
• Traditional/published 4Gb/day social media
  10gb/day from Andrew Tomkins/Yahoo!, Future or
  Web Search, May 2007
• Research challenges
• Low(er) quality
• Content more dynamic
• User interactions crucial
• ratings, comments, link structure
• to retrieve documents and to
• evaluate extracted information

2
Finding High Quality Content for IE/QA
E. Agichtein, C. Castillo, D. Donato, A. Gionis,
G. Mishne, Finding High Quality Content in
Social Media, in Proc. of WSDM 2008

• Goal find high-quality content (accurate
  well-presented)
• Setting Community QA (Yahoo! Answers)
• Classifying social media (e.g., cQA) is
  substantially different from document
  classification
• Sources of information
• Content analysis
• Usage data (page views, etc)
• Community ratings, link analysis
• General framework for quality estimation in
  social media
• Graph-based model of contributor relationships,
  combined with content and usage analysis
• Can identify high-quality items with accuracy
  human agreement

3
Finding Relevant Content for IE/QA
J. Bian, Y. Liu, E. Agichtein and H. Zha. Finding
the Right Facts in the Crowd Factoid Question
Answering over Social Media, to appear in Proc.
of WWW 2008

• Goal given a query, rank social content (cQA) by
  expected relevance and quality
• Approach Learn ranking functions specifically
  for social media retrieval
• Features
• Textual content relevance, stylistics, language
  models
• User Interactions link structure, discussion
  threads
• User ratings incorporate user-provided content
  ratings
• Method Gradient boosting (GBrank)
• Developed a new objective function for learning
  ranking function using (noisy) preference data.
• Results
• Outperform Yahoo! default ranking or naïve
  ranking by user votes
• Can be made robust to ratings spam same
  authors, to appear in AIRWeb 2008