Past seminars at the Faculty of Informatics

Why Extremely Short Queries Are Popular?

The Faculty of Informatics is pleased to announce a seminar given by Kalervo Järvelin

DATE: Monday, January 25th, 2010
PLACE: USI Università della Svizzera italiana, room SI-008, Informatics building (Via G. Buffi 13)
TIME: 15.30

There is overwhelming evidence suggesting that the real users of IR systems often prefer using extremely short queries (one or two individual words) but they try out several queries if needed. Such behavior is very different from the process modeled in traditional test collection-based IR evaluation based on using more verbose queries and only one query per topic.  In this talk we will evaluate sequences of short queries as sessions based on empirically grounded session strategies. We employ a TREC test collection with graded relevance judgments and simulate sessions based on session strategies for repeatability and control. The experimental results indicate that web-like very short queries (including one-word query sequences) typically lead to good enough results even in a TREC type test collection. This finding motivates the observed real user behavior: as few very simple attempts normally lead to good enough results, there is no need to pay more effort. We conclude by discussing the consequences of our finding for IR evaluation.

Kal Järvelin ( is Professor at the Dept. of Information Studies and Interactive Media, University of Tampere. He holds a PhD in Information Studies (1987) from the same university.
Kal’s research covers information seeking and retrieval, and database management; and linguistic and conceptual methods in IR. He has authored some 250 scholarly publications and supervised fifteen doctoral dissertations. His H-index is 24 in Google Scholar (December 2009). He has been the principal investigator of numerous research projects funded by EU, industrial organizations and the Academy of Finland.
Kal has served the ACM SIGIR Conferences as a program committee member (1992-2005), Conference Chair (2002) and Program Co-Chair (2004, 2006). He is an Associate Editor of Information Processing and Management (USA).

HOST: Prof. Fabio Crestani