博弈论ir 2015 dais信息检索框架成.pdf

Towards a Game-Theoretic Framework for Information Retrieval ChengXiang (“Cheng”) Zhai Department of Computer Science University of Illinois at Urbana-Champaign : czhai@ Yahoo!-DAIS Seminar, UIUC, Jan 23, 2015 1 Search is everywhere, and part of everyone’s life Web Search Desk Search Enterprise Search Social Media Search Site Search … … 2 Search accuracy matters! # Queries /Day X 1 sec X 10 sec 4,700,000,000 ~1,300,000 hrs ~13,000,000 hrs 1,600,000,000 ~440,000 hrs ~4,400,000 hrs 3,000,000 ~550 hrs ~5,500 hrs … … How can we optimize all search engines in a general way? Sources: : . / -searches/ : . / -statistics/ PubMed: searches.html 3 How can we optimize all search engines in a general way? However, this is an ill-defined question! What is a search engine? What is an optimal search engine? What should be the objective function to optimize? 4 Current-generation search engines collection number of queries search engines k