计算机科学与技术系

Department of Computer Science and Technology

Education background

Bachelor of Computer Science & Technology, Tsinghua University, Beijing, China, 1982;

Master of Computer Science & Technology, Tsinghua University, Beijing, China, 1984;

Ph.D. in Computer Science & Technology, Tsinghua University, Beijing, China, 1997.

Social service

State Key Lab of Intelligent Technology and Systems, Tsinghua University: Director (2004-);

Chinese Association for Artificial Intelligence: Executive Council Member (2006-);

Chinese Information Processing Society of China: Council Member (2006-);

Areas of Research Interests/ Research Projects

Web Information Processing, Information Retrieval

National Natural Science Foundation of China: Next-Generation Web Information Retrieval (2008-2011);

National Basic Research Program of China (The 973 Program): Content-based Multimedia Information Retrieval (2005-2009);

"Tsinghua-Sohu" Joint Lab on Web Search Technology Research Foundation: Behavior Analysis of Search Engine Users, Behavior Analysis of Chinese Input Method, Query Recommendation for Search Engine, Web Spam Page Identification, etc (2010-2012).

Research Status

I am generally interested in the research areas of intelligent information processing, information retrieval, and Web data mining. Among them, I have been recently focusing on improving search performance with the help of semantic mining of user behaviors.

Due to the giant volume of Web information and limitations of current intelligent technologies, semantic analysis of on-line data faces lots of challenges. While billions of users are surfing the Web each day by means of direct typing of domain name, hyperlink on existing Web pages, or search engines, it is believed that their behaviors contain certain semantic information, which can be further utilized to help us better understand the semantic meanings of online data. Therefore, we work on this kind of information with the aim of improving the performance of Web search engines.

Our recent projects span over Web page quality estimation, Web spam page and illegal resource identification, search performance evaluation, on-line advertising performance evaluation, and search engine query recommendation. We have published a dozen of high-quality papers at important journals and conferences such as JASIST, WWW, CIKM, and WSDM. 8 Chinese patents were filed and 3 of them have been authorized. Algorithms and systems developed in these projects have been successfully adopted by Sogou.com, one of the most popular search engines in China.

Demos of our research projects can be found at SearchE Search Engine Performance Evaluation System (http://searche.thuir.cn/), and Sogou.com Laboratory (http://www.sogou.com/labs).

Academic Achievement

[1] Rongwei Cen, Yiqun Liu, Min Zhang, Bo Zhou, Liyun Ru, Shaoping Ma. Exploring Relevance for Clicks. In Proceeding of the 18th ACM Conference on information and Knowledge Management (CIKM '09). Hong Kong, China, pp. 1847-1850.

[2] Yiqun Liu, Yijiang Jin, Min Zhang, Shaoping Ma and Liyun Ru. User Browsing Graph: Structure, Evolution and Application. Late breaking result session in Second ACM International Conference on Web Search and Data Mining (WSDM 2009). 2009.2

[3] Yiqun Liu, Rongwei Cen, Min Zhang, Shaoping Ma. Automatic Search Engine Evaluation Based On User Behavior Analysis (in Chinese). Journal of Software, Vol.19(11):3023-3032. 2008.11.

[4] Canhui Wang, Min Zhang, Liyun Ru, Shaoping Ma. Automatic Online News Topic Ranking Using Media Focus and User Attention Based on Aging Theory, In Proceedings of the ACM 17th Conference on Information and Knowledge Management (CIKM 2008), October 26-30, 2008, Napa Valley California, USA. pp1033-1042

[5] Canhui Wang, Min Zhang, Shaoping ma, Liyun Ru, Automatic Online News Issue Construction in Web Environment, the 17th International World Wide Web Conference (WWW2008), Beijing, April, 2008, pp457-466

[6] Yiqun Liu, Min Zhang, Shaoping Ma, Liyun Ru. User Behavior Oriented Web Spam Detection, the 17th International World Wide Web Conference (WWW2008), poster, Beijing, April, 2008, pp1039-1040

[7] Yiqun Liu, Min Zhang, Liyun Ru, Shaoping Ma. Data Cleansing for Web Information Retrieval using Query Independent Features. Journal of the American Society for Information Science and Technology (JASIST), Volume 58, Issue 12, Pages 1884-1898, 2007

[8] Yiqun Liu, Yupeng Fu, Min Zhang, Shaoping Ma, Liyun Ru. Automatic Search Engine Performance Evaluation with Click-through Data Analysis. to be appeared at the 16th World Wide Web conference (WWW07), 2007, Banff, Canada. Web application top conference. p1133~1134

[9] Yupeng Fu, Rongjing Xiang, Yiqun Liu, Min Zhang, Shaoping Ma. A CDD-based Formal model for Expert Finding. In *Proceedings of the ACM Sixteenth Conference on Information and Knowledge Management (CIKM 2007), p881-884,Lisboa, Portugal, November 2007.

[10] Le Zhao, Min Zhang, Shaoping Ma. The Nature of Novelty Detection, Information Retrieval,vol 9(5): 521-542, 2006