Wednesday, April 27, 2011

ECIR 2011 + DDR 2011 in Dublin

Last week, a few of us attended ECIR 2011 in Dublin. The conference was a resounding success both in terms of its program and organisation. Compared to last year, the event was very well attended with about 250 delegates registered to the conference and/or its satellite events. The majority of delegates were from Ireland and the United Kingdom.

Workshops

The kick-off was on Monday, with a selection of workshops and tutorials at the fabulous Guinness Storehouse. We attended the Diversity in Document Retrieval (DDR 2011) workshop, jointly organised by Craig Macdonald, Jun Wang, and Charlie Clarke.

The DDR workshop was sometimes a standing-room only event and appeared to be the largest workshop of the conference. It was structured around three broad themes: evaluation, modelling, and applications. Besides good keynotes by Tetsuya Sakai and Alessandro Moschitti, the workshop featured technical and position paper presentations, as well as a poster session and a breakout group discussion on all three workshop themes. While there was no agreement on a possible "killer application" for diversity, there was a consensus that diversity is best described or seen as the lack of context. In addition, a few key points arose across the boundaries of the tackled themes:
  • Representing diversity
    How to best represent the possible multiple information needs underlying a query? Should this representation reflect the interests of the user population, or should it be itself diverse?
  • Measuring diversity
    What does diversity mean and how should it be promoted in different scenarios? The workshop featured some ideas for applications, including expert search, geographical IR, and graph summarisation.
  • Unifying diversity
    How to diversify across multiple search scenarios (e.g., multiple verticals of a search engine)? How to convey a summary relevant to multiple information needs in a single page of results?
Some of these ideas are currently being investigated as part of the NTCIR-9 Intent task. Charlie was also keen to consider these questions in future incarnations of the diversity task in the TREC Web track. During the workshop, Rodrygo presented our position paper entitled "Diversifying for multiple information needs". The full DDR workshop proceedings are available online.

While we haven't attended it, it was of note that the Information Retrieval Over Query Sessions workshop, which was held at the same time as DDR, also received very good and positive feedback from its attendees.

The workshops were followed by an excellent welcome reception where the least we could say is that Guinness was not in shortage.

Conference

On Tuesday, the main conference took over with a diverse (no pun intended) program. The conference started with a thoughtful keynote by Kalervo Järvelin who urged the information retrieval community to see beyond the [search] box. The keynote led to some very interesting discussions about whether IR is a science or a technology (i.e. mostly about engineering). We would like to believe that it is science, although some delegates argued (sadly) for the opposite.

The second keynote was given by Evgeniy Gabrilovich, winner of this year's KSJ Award. Evgeniy provided a very comprehensive overview of the fascinating computational advertising field, highlighting the current state-of-the-art and possible future research directions. We were encouraged to hear about the Yahoo! Faculty Research and Engagement Program (FREP), which might allow academics to access the necessary datasets to conduct research in a field that has been thus far the sole territory of researchers based in industry.

The last keynote talk was superbly given by Thorsten Joachims about the value of user feedback. Thorsten convincingly argued for the importance of collecting user feedback as an intrinsic part of both the retrieval and learning processes. The talk highlighted how user feedback could improve the quality of retrieval and by how much. We wish that the slides will be made publicly available at some point.

As for the rest of the program, there were two types of papers/presentations: full papers were presented in 30 min, while short papers had only 15 min. As usual, the quality of papers (or at least the presentations) varied from the outstanding to the less good. One suggestion for future ECIR conferences is to limit all the talks to at most 20 min, encouraging conciseness and pushing the speakers to focus on the "message out of the bottle". Indeed, some talks appeared to be exceedingly long with respect to their informative content. While we see the value of giving a 30 min slot to a 10-pages long ACM-style paper, there does not seem to be a valid reason for giving that much time for a (comparatively much shorter) 12-pages LNCS-style paper.

It was interesting to see several Twitter-related papers in the program, suggesting that the community will find the upcoming new TREC 2011 Microblog track and its corresponding shared dataset particularly useful/helpful. The theme of crowdsourcing was also highly featured in the conference, with several papers showing how cheap and reliable relevance assessments could be obtained through the Amazon Mechanical Turk or similar services. Finally, we were very pleased to see many presented papers using our open source Terrier software in their experiments.

Overall, a few papers caught our attention and were particularly interesting:
  • On the contributions of topics to system evaluation
    Steve Robertson
  • Caching for realtime search - in our opinion by far the best paper/presentation of the conference
    Edward Bortnikov, Ronny Lempel and Kolman Vornovitsky
  • Are semantically related links effective for retrieval?
    Marijn Koolen and Jaap Kamps
  • A methodology for evaluating aggregated search results - Excellent paper/presentation that was also awarded the best student paper award
    Jaime Arguello, Fernando Diaz, Jamie Callan and Ben Carterette
  • Design and implementation of relevance assessments using crowdsourcing
    Omar Alonso and Ricardo Baeza-Yates
  • The power of peers
    Nick Craswell, Dennis Fetterly and Marc Najork
  • Automatic people tagging for expertise profiling in the enterprise
    Pavel Serdyukov, Mike Taylor, Vishwa Vinary, Matthew Richardson and Ryen W. White
  • What makes re-finding information difficult? A study of email re-finding
    David Elsweiler, Mark Baillie and Ian Ruthven
Of course, we also recommend our own paper, which was nominated for best paper award, and for which we received excellent feedback:
The program also featured a busy poster and demo session. We liked the work of Gerani Keikha, Carman and Crestani concerning identifying personal blogs using the TREC Blog track, and that of Perego, Silvestri and Tonellotto, which suggests that document length can be quantized from docids without loss of retrieval effectiveness. There were also several interesting demos that caught our eye:
  • ARES - A retrieval engine based on sentiments: Sentiment-based search result annotation and diversification - which used our xQuAD framework for diversifying sentiments
    Gianluca Demartini
  • Conversation Retrieval from Twitter
    Matteo Magnani, Danilo Montesi, Gabriele Nnziante and Luca Rossi
  • Finding Useful Users on Twitter: Twittomender the Followee Recommender - addressed the Who to Follow (WTF?) task on Twitter
    John Hannon, Kevin McCarthy and Barry Smyth
The ECIR organisers hosted a particularly sumptuous conference banquet at the impressive, unique and beautiful venue of The Village at Lyons Demesne in County Kildare. The journey to the village was a welcome break from the hotel setting of the conference and its technical program.

On the last day of the conference, and concurrently to the technical research sessions, an Industry Day event was under way. However, we only had the chance to go and see the excellent talk by Flavio Junqueira on the practical aspects of caching in search engine deployments. There is a comprehensive summary of the whole Industry program in this blog post. We believe that the planning of the Industry Day event in parallel to the technical sessions was detrimental to attendance. Next year, the Industry Day will be held after the conference ends.

Finally, we would like to thank the organisers of ECIR 2011 for a very enjoyable conference, and a great stay in Dublin. ECIR 2012 will be held in Barcelona, Spain, between 1st and 5th April 2012. We hope to see you all there.

Friday, November 26, 2010

TREC 2010 Roundup

Back from another successful TREC conference on the NIST campus. 2010 is a transition year, with the end of old tracks and the proposition of new ones. Indeed, TREC is moving with the times, looking at new data sources and test collections, as well as new evaluation strategies.

Outwith the old . . .

For example, TREC 2010 marks the end of the Relevance Feedback and Blog tracks. While TREC 2010 will be the last year of the Relevance Feedback track, the Blog track, which has been running for the last 5 years, is now morphing into a new Microblog track, investigating real-time and social search tasks in Twitter. A brand new test collection possibly containing 2 months of tweets is planned, with linked web-pages and a partial follower graph. Join the Microblog track googlegroup to obtain the latest updates and follow the Microblog track on Twitter.

TREC 2011 will also witness the initiation of the new Medical Records track, dedicated to investigating approaches to access free-text fields of electronic medical records.

On the test collection front, the Web track is also forward planning a new large-scale dataset to replace ClueWeb09. Indications are that this new dataset will be about the same scale as ClueWeb09 but might provide more temporal information (multiple versions of a page or site over time). Moreover, we have suggested that this might be the heart of a larger dataset comprised of multiple parallel/aligned corpora, for example blogs and news feeds covering the same timeframe.

TREC Assessors, Relevant?

In terms of evaluation, 2010 marks the first year where evaluation judgments were crowdsourced using an online worker marketplace, as opposed to relying on TREC assessors, the participants themselves, or a select group of experts. Indeed, both the Blog track and the Relevance Feedback track crowdsourced some of their evaluation (although the Relevance Feedback track suffered many setbacks and its crowdsourcing process is still incomplete). Furthermore, to investigate the challenges in this new field of crowdsourcing, a specific Crowdsourcing track has been created and will run in 2011. More details can be found here.

Themes

As usual, themes emerged within the various tracks. Learned approaches were far more prevalent this year, now that training data was available for the ClueWeb09 dataset. Indeed, the Web track was dominated by trained models mostly based on link and proximity search features. Diversification, on the other hand, remains a challenging task, with the top groups leaving their initial rankings as is. An outstanding exception is our own approach using the xQuAD framework under a selective diversification regime, which further improves our strongly performing adhoc baseline. Craig Macdonald presented our work in the Web track plenary session.

In the Blog track, voting model-based and language modeling approaches proved popular for blog distillation. For faceted blog ranking, participants employed variants of facet dictionaries to either train a classifier or as features for learning. For the top news task, participants deployed a wide variety of methods to rank news stories in a real-time setting, from probabilistic modeling to blog post voting with historical evidence. Richard Mccreadie presented our work on the blog track as a poster during TREC 2010, which attracted very interesting discussions.

During the TREC conference, Iadh Ounis, Richard Mccreadie and others have done a fair amount of tweeting. You can follow some bits of the TREC conference through the #trec2010 hashtag.

Wednesday, November 3, 2010

CIKM 2010 in Toronto, ON, Canada

I'm back from Toronto, where a few of us attended the CIKM 2010 conference last week. On Friday, I presented our paper on "Selectively diversifying Web search results", a joint work with Craig Macdonald and Iadh Ounis. This work extends our successful participation in the diversity task of the TREC 2009 Web track, by investigating the need for search result diversification in the first place. In particular, we proposed a novel supervised learning approach to predict not only whether promoting diversity is beneficial, but also how much diversification should be applied to attain an effective retrieval performance on a per-query basis. After thorough, large-scale experiments with over 900 query features, we found that our selective approach can substantially improve existing diversification approaches, including our state-of-the-art xQuAD framework. Nonetheless, we believe the significance of our contribution goes beyond these successful results. Indeed, it was with great pleasure that we heard from the NTCIR organisers that NTCIR-9 will run an Intent task, aimed---among other things---at selectively diversifying search results, an area where we are proud to be pioneers.
Besides our own paper, a few other papers caught my attention:
  • Web Search Solved? All Result Rankings the Same? by Hugo Zaragoza, B. Barla Cambazoglu and Ricardo Baeza-Yates
  • Reverted Indexing for Feedback and Expansion, by Jeremy Pickens, Matthew Cooper and Gene Golovchinsky
  • Rank Learning for Factoid Question Answering with Linguistic and Semantic Constraints, by Matthew Bilotti, Jonathan Elsas, Jaime Carbonell and Eric Nyberg
  • Organizing Query Completions for Web Search, by Alpa Jain and Gilad Mishne
  • Clickthrough-Based Translation Models for Web Search: from Word Models to Phrase Models, by Jianfeng Gao, Xiaodong He and Jian-Yun Nie
The conference also featured great keynotes, of which those by Jamie Callan and Susan Dumais deserve a particular mention. Jamie talked about his view for the future of search, in which search engines capable of fully leveraging the structure of queries and documents would enable more sophisticated applications built on top of them. Susan addressed the temporal evolution of Web content, how it impacts the way users access this content, and how test collections should account for it. For more details, have a look at the excellent posts by Gene Golovchinsky on Jamie and Susan's talks.
Last but not least, many of us were involved in promoting the next edition of CIKM, to be held here in Glasgow. There was a lot of excitement from the several people that visited our booth, and also during the hand-over talk at the end of the conference. Well done Jon, Mary, Craig, and Iadh for the hard work! The arrangements for CIKM 2011 are well advanced, and the call for papers is now online. You can also follow the latest news about CIKM 2011 on Twitter, Facebook, LinkedIn, and Lanyrd. We look forward to welcoming you all to Glasgow next year!

Tuesday, July 20, 2010

Terrier Team at SIGIR 2010 in Geneva

SIGIR 2010 has just started in Geneva. From the TerrierTeam, Richard and myself are attending.

On Monday, Richard presented his PhD topic, Leveraging User-generated Content for News Search at the doctoral consortium.

Later, at the Web Ngram workshop, I'll be presenting a paper on Global Statistics in Proximity Weighting Models.

About the same time, Richard will be presenting at the Crowdsourcing for Search Evaluation workshop. His paper on Crowdsourcing a News Query Classification Dataset examines the effectiveness of different interfaces for having Mechanical Turkers classify queries as news-related or not.

Last but not least, and continuing on our proximity theme, Nicola Tonellotto from CNR is presenting our joint work titled Efficient Dynamic Pruning with Proximity Support at the Large Scale & Distributed Systems workshop.

Meanwhile, please say hello if you see us at the conference, or stay up to date by following #sigir2010. And remember, if you are near the registration desk, please pick up flyers for Terrier and CIKM 2011.

Monday, July 19, 2010

Top Authors in Information Retrieval

Thanks to Sérgio Nunes who alerted us to this ranking by Microsoft Academic Search of the Top Authors in Information Retrieval, in the past 5 years.

According to this recent ranking, two members of the TerrierTeam, namely Iadh Ounis and Craig Macdonald, are in the top 5 authors in Information Retrieval in the past 5 years (position #1 and #4, respectively). The ranking is based on in-domain citations.

This good news comes just at the start of the SIGIR 2010 Conference, which will be held in Geneva, Switzerland this week (19-23 July 2010). Several members of the team will be in attendance.