The sixth Dutch-Belgian Information Retrieval
workshop (DIR 2006)
Wessel Kraaij, TNO ICTFranciska de Jong, TNO ICT and University of Twente
The Netherlands

1Introduction

The 6th issue of the Dutch-Belgian Information Retrieval workshop took place at
March 13 and 14, 2006 and was hosted by TNO Information and Communication
Technology in Delft, The Netherlands. The primary aim of the DIR workshops
is to provide an international meeting place where researchers from the domainof information retrieval and related disciplines, can exchange information andpresent new research developments. This year, there was a special focus oncontributions focusing on domain-specific retrieval tasks.
The workshop is organised under the auspices of the Dutch Working Community on Information Sciences (WGI). TNO ICT is the organising instituteand additional support comes from the Human Media Interaction group (HMI
University of Twente), the Dutch Research School for Information and Knowledge Systems (SIKS), Netherlands Bioinformatics Centre (NBIC), Nederlandse
Organisatie voor Wetenschappelijk Onderzoek (NWO Exacte Wetenschappen),and the Taalunie-programme STEVIN.

2Presentations

The first keynote by ChengXiang Zhai (UIUC) focused on domain specific IR,in particular bioinformatics. His presentation started out with a tutorial onsome of the problems in bioinformatics and demonstrated the relevance of IRtechniques. He concluded his presentation with several challenges for IR inspiredby bioinformatics.
Leif Azzopardi unfortunately could not make it to the workshop, but submitted his presentation about query intention acquisition, evaluated using datafrom the enterprise track. Several LM based retrieval models were tested, someof which were less robust than others.
Vojkan Mihaljovic (University of Twente) presented work on vague elementselection in the context of the INEX. The extensions to the TIJAH framework1resulted in a higher recall for vague element name selection and a higher precision for rewriting techniques.
Kees van der Meer (Delft University) discussed some solutions to practicalproblems related to construct an XML based data container including metadata
for long-term storage of hydrology datasets with inherent authenticity guarantee. The presentation raised an interesting discussion on the scope and usage
scenarios of Dublin Core versus metadata element schemes such as OAIS.
Willem van Hage announced the OAEI an initiatve aiming at a controlled
evaluation of the alignment of ontologies. The workshop will be run for thethird time this year http://oaei.ontologymatching.org/2006/.
Anni Jarvelin presented research from the University of Tampere on Crosslanguage Information Retrieval between closely related languages. Experiments
showed that for related language pairs, translation dictionaries might not berequired, since n-gram term matching can yield quite acceptable performance.
Skipgrams turned out to be the most effective.
Fotis Lazarinis submitted work about information extraction techiques for
Greek texts, but did not attend the workshop.
Gijs Geleijnse presented a pattern based approach to information extraction.
A system has been designed and evaluated to query a web search engine andfill templates in an ontology, e.g. attributes of a movie (title, director, actors).
Also an algorithm to determine the most famous people was presented. Most ofthem had German nationality, which gave plenty of room for discussion on thequality of the algorithm.
The second workshop day started with a keynote lecture of Maarten de Rijke entitled ”facing restrictions in QA”. Maarten first discussed the XIRAF
architecture, which extends XQuery with stand-off XML. Xiraf enables structured queries that leverage multiple annotation levels. StandOff axes. As asecond example of restrictions, he presented specialized presentation methods
such as WikiTimeLine, where time information helps to structure different facts
www.wikitimeline.net. Finally Maarten presented an idea to use the highly
structured wikipedia biography pages as a skeleton for generating biographicalsummaries, by means of sentence voting.
Toine Bogers discussed expert search.in workgroups. His method computes
the informativeness of a term for an author. Subsequently a baseline cosine
system with an author based authority score. The method had significant improvement on CACM, but not on two other small collections.
Claudia Hauff discussed scale free networks to describe citation networks.
Her Hypothesis was: importance indicator and reference graph help users. A
user study showed a positive tendency, although not unanimous.
Vera Hollink presented an experiment comparing different methods for search
result presentation. Three methods were compared: list vs, hierarchical structure vs. Information Gain. Conclusion is that IG achieves the best results
because it balances ”using information” vs. ”collecting information”. Label
quality is very important, since poor labels will induce backtracking search behaviour.
2Jaap Kamps (University of Amsterdam) presented work on Wikipedia. He
first advertised its use as a research corpus: ”It’s large, free and FUN!” , general,
highly structured and densely linked. Secondly he presented an experiment
where a baseline (page based) search system was compares with a focused system
returning section level snippets. The evaluation did not provide a clear answers
whether users like focused access than the baseline system. But time to solve
task was decreased.

3Conclusions

The DIR 2006 workshop was a success, with some 40 attendees including many
PhD students and several information professionals and even representatives
form industry. The full proceedings of the workshop including the presentation
slides can be found on: http://hmi.ewi.utwente.nl/dir2006/program.php.
In 2007, DIR will be hosted by the Katholieke Universiteit Leuven in Belgium.

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