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, 2003;

Ph.D. in Computer Science & Technology, Tsinghua University, Beijing, China, 2007

Social service

Department of Computer Science and Technology: Supervisor of Undergraduate Mentors (2006-);

The 3rd National Computational Linguistic Workshop of Young Scholars (SWCL 2006): Program Committee Chair (2006).

Areas of Research Interests/ Research Projects

Web Information Retrieval, User Behavior Analysis, Natural Language Processing

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

National Natural Science Foundation of China:Web Spam Page identification Based on User Behavior Analysis (2010-2012);

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

Research Status

I'm generally interested in the research areas of Web search technology and Web user behavior analysis, and have particular focus on improving search performance with the help of user behavior analysis.

Current commercial search engines face great challenges in the rapid growth of WWW data and user requests. In order to improve their performance, we believe that the behavior information of search users, so called "wisdom of the crowd", can be utilized. With the support of National Natural Science Foundation of China and "Tsinghua-Sohu" Joint Lab on Web Search Technology, tangible progresses were made in this direction.

The aspects of our recent projects cover 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 several high-quality papers in JASIST, WWW, CIKM, WSDM, and some other important journals and conferences. 8 Chinese patents were filed, 3 of which were authorized. Algorithms and systems developed from these projects have been 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 home page (http://www.sogou.com/labs).

Honors And Awards

"Lin Feng" Excellent Student Mentor Award, Tsinghua University (2008)

Academic Achievement

[1] 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, 2007.10.

[2] Yiqun Liu, Rongwei Cen, Min Zhang, Shaoping Ma, Liyun Ru. Identifying Web Spam with User Behavior Analysis. The Fourth International Workshop on Adversarial Information Retrieval on the Web. 2008.4.

[3] Yiqun Liu, Yijiang Jin, Min Zhang, Shaoping Ma, 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).

[4] Liu, Y., Zhang, M., Ma, S., and Ru, L. 2008. User behavior oriented web spam detection. In Proceeding of the 17th international Conference on World Wide Web (Beijing, China, April 21 - 25, 2008). WWW '08. ACM, New York, NY, 1039-1040.

[5] Rongwei Cen, Yiqun Liu, Min Zhang, Bo Zhou, Liyun Ru, Shaoping Ma. Exploring Relevance for Clicks. In Proceedings of The 18th ACM Conference on Information and Knowledge Management. (CIKM'09) 2009.

[6] Rongwei Cen, Yiqun Liu, Min Zhang, Liyun Ru, Shaoping Ma. Web Observation from a User Perspective. In Proceedings of the 2009 IEEE/WIC/ACM international Joint Conference on Web intelligence and intelligent Agent Technology - Volume 01. IEEE Computer Society, Washington, DC, 291-294.

[7] Yiqun Liu, Canhui Wang, Min Zhang, Shaoping Ma, Web Data Cleansing for Information Retrieval using Key Resource Page Selection, Proceedings of the 14th International World Wide Web conference, Pages 1136-1137, 2005.

[8] Yiqun Liu, Yupeng Fu, Min Zhang, Shaoping Ma, Liyun Ru. Automatic Search Engine Performance Evaluation with Click-through Data Analysis. in Proceedings of the 16th international Conference on World Wide Web (Banff, Alberta, Canada, May 08 - 12, 2007). WWW '07. ACM, New York, NY, 1133-1134.

[9] Yiqun Liu, Canhui Wang, Min Zhang, Shaoping Ma, Finding "Abstract Fields" of Web Pages and Query Specific Retrieval--THUIR at TREC 2004 Web Track, NIST Special Publication: SP 500-261, Proceedings of the Thirteenth Text Retrieval Conference (TREC 2004).

[10] Yiqun LIU, Bo ZHOU, Min ZHANG, Shaoping MA, Liyun RU, Effectiveness of Online Sponsored Search Based on User Log Analysis. Journal of Computational Information Systems. Vol.5(3): pp. 1175-1184. 2009.

[11] Yiqun Liu, Canhui Wang, Min Zhang, Shaoping Ma, Learning-based Web Data Cleansing for Information Retrieval, Journal of Computational Information Systems, Vol 1(n4): pp. 709-716, 2005.

[12] Qianli Xing, Yiqun Liu, Rongwei Cen, Min Zhang, Shaoping Ma, Liyun Ru: Are search engine users equally reliable WWW 2010: 1207-1208.

[13] Weize Kong, Yiqun Liu, Shaoping Ma, Liyun Ru: Detecting epidemic tendency by mining search logs. WWW 2010: 1133-1134.

[14] Rongwei Cen, Yiqun Liu, Min Zhang, Liyun Ru, Shaoping Ma: Study language models with specific user goals. WWW 2010: 1073-1074.

[15] 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.

[16] Yiqun Liu, Min Zhang, Shaoping Ma. Web Key Resource Page Selection Based On Improved Decision Tree Algorithm. (in Chinese) Journal of software, Vol. 16(11): pp. 1958-1966, 2005.

[17] Shaoping Ma, Yiqun Liu. Method for finding needle in a haystack: Techniques and challenges in Chinese Web information retrieval (in Chinese). Communications of China Computer Federation, 2008.1.

[18] Yiqun Liu, Shaoping Ma, Tao Hong and Zizheng Liu. Fundamentals in Search Engine Technology. Tsinghua University Press, Beijing, China, 2010.