CS Colloquium Series @ UCY
Department of Computer Science - University of Cyprus
The Department of Computer Science at the University of Cyprus holds research colloquiums and social hours approximately once weekly. All university students, faculty, and staff are invited to attend. Notifications about new and upcoming events are automatically disseminated to a variety of institutional lists.
If you don't receive these notifications, but want to get informed about upcoming colloquium announcements, you can do the following:
List
RSS
Directions
Colloquium Coordinator: Demetris Zeinalipour
Colloquium: Diverse and Proportional Size-l Object Summaries for Keyword Search, Dr. Georgios J. Fakas (Hong Kong University of Science and Technology, Hong Kong), Wednesday, April 8, 2015, 11:00-12:00 EET.
The Department of Computer Science at the University of Cyprus cordially invites you to the Colloquium entitled:
Diverse and Proportional Size-l Object Summaries for Keyword Search
 |
Speaker: Dr. Georgios J. Fakas |
Abstract:
The abundance and ubiquity of big graphs (e.g., Online Social Networks
such as Google+ and Facebook; bibliographic graphs such as DBLP)
necessitates the effective and efficient search over them. Given a set
of keywords that can identify a Data Subject (DS), a recently proposed
relational keyword search paradigm produces, as a query result, a set
of Object Summaries (OSs). An OS is a tree structure rooted at the DS
node (i.e., a tuple containing the keywords) with surrounding nodes
that summarize all data held on the graph about the DS. OS snippets,
denoted as size-l OSs, have also been investigated. Size-l OSs are
partial OSs containing l nodes such that the summation of their
importance scores results in the maximum possible total score.
However, the set of nodes that maximize the total importance score may
result in an uninformative size-l OSs, as very important nodes may be
repeated in it, dominating other representative information. In view
of this limitation, in this paper we investigate the effective and
efficient generation of two novel types of OS snippets, i.e. diverse
and proportional size-l OSs, denoted as DSize-l and PSize-l OSs.
Namely, apart from the importance of each node, we also consider its
frequency in the OS and its repetitions in the snippets. We conduct an
extensive evaluation on two real graphs (DBLP and Google+). We verify
effectiveness by collecting user feedback, e.g. by asking DBLP authors
(i.e. the DSs themselves) to evaluate our results. In addition, we
verify the efficiency of our algorithms and evaluate the quality of
the snippets that they produce.
Short Bio:
Georgios J. Fakas is a Post-Doctoral Research Fellow in the Department
of Computer Science and Engineering at the Hong Kong University of
Science and Technology. He also worked as a Senior Lecturer at the
Manchester Metropolitan University, UK and as a Research Fellow at the
University of Hong Kong, Hong Kong and at the Swiss Federal Institute
of Technology - Lausanne (EPFL), Switzerland. He obtained his Ph.D. in
Computation in 1998 from the Department of Computation, UMIST,
Manchester, UK. His research interests include databases, keyword
search and ranking.
Sponsor: The CS Colloquium Series is supported by a generous donation from  |