CI-Rank: Ranking Keyword Search Results Based on Collective Importance

Speaker:        Dr. Xiaohui YU
                School of Information Technology
                York University
                Canada

Title:          "CI-Rank: Ranking Keyword Search Results Based on
                Collective Importance"

Date:           Monday, 16 January 2012

Time:           11:00am - 12 noon

Venue:          Room 3416 (via lifts 17/18), HKUST

Abstract:

Keyword search over databases, popularized by keyword search in WWW,
allows ordinary users to access database information without the knowledge
of structured query languages and database schemas. Most of the previous
studies in this area use IR-style ranking, which fail to consider the
importance of the query answers. We propose CI-Rank, a new approach for
keyword search in databases, which considers the importance of individual
nodes in a query answer and the cohesiveness of the result structure in a
balanced way. CI-Rank is built upon a carefully designed model call Random
Walk with Message Passing that helps capture the relationships between
different nodes in the query answer. We develop a branch and bound
algorithm to support the efficient generation of top-k query answers.
Indexing methods are also introduced to further speed up the run-time
processing of queries. Extensive experiments conducted on two real data
sets with a real user query log confirm the effectiveness and efficiency
of CI-Rank.

********************
Biography:

Xiaohui Yu is an associate professor in the School of Information
Technology at York University, Canada. He also holds an specially
appointed professorship at Shandong University, China under the Taishan
Overseas Scholar Program. He obtained his PhD degree in Computer Science
from the University of Toronto. His research interests lie in the areas of
database systems and data mining. He has published around 30 papers in
premier venues, including SIGMOD, VLDB, ICDE, EDBT, SIGIR, and ICDM. He
has served on the program committees/review boards of various conferences,
such as VLDB'11 and CIKM'11, and was the program co-chairs of two
international workshops. His research has been supported by national
funding agencies in Canada and China, and he has had extensive
collaboration with companies in the industry, such as IBM and AT&T. He is
an IBM CAS Faculty Fellow, and he received the Dean's Award for Excellence
in Research in 2009.