Evaluation Of Cross Language Information Retrieval Systems

The second evaluation campaign of the Cross Language Evaluation Forum (CLEF) for European languages was held from January to September 2001. This campaign proved a great success, and showed an increase in participation of around 70% com pared with CLEF 2000. It culminated in a two day workshop in Darmstadt, Germany, 3–4 September, in conjunction with the 5th European Conference on Digital Libraries (ECDL 2001). On the first day of the workshop, the results of the CLEF 2001 evalua tion campaign were reported and discussed in paper and poster sessions. The second day focused on the current needs of cross language systems and how evaluation cam paigns in the future can best be designed to stimulate progress. The workshop was attended by nearly 50 researchers and system developers from both academia and in dustry. It provided an important opportunity for researchers working in the same area to get together and exchange ideas and experiences. Copies of all the presentations are available on the CLEF web site at http://www. clef campaign. org. This volume con tains thoroughly revised and expanded versions of the papers presented at the work shop and provides an exhaustive record of the CLEF 2001 campaign. CLEF 2001 was conducted as an activity of the DELOS Network of Excellence for Digital Libraries, funded by the EC Information Society Technologies program to further research in digital library technologies. The activity was organized in collabo ration with the US National Institute of Standards and Technology (NIST).

Search for information is no longer exclusively limited within the native language of the user, but is more and more extended to other languages. This gives rise to the problem of cross-language information retrieval (CLIR), whose goal is to find relevant information written in a different language to a query. In addition to the problems of monolingual information retrieval (IR), translation is the key problem in CLIR: one should translate either the query or the documents from a language to another. However, this translation problem is not identical to full-text machine translation (MT): the goal is not to produce a human-readable translation, but a translation suitable for finding relevant documents. Specific translation methods are thus required. The goal of this book is to provide a comprehensive description of the specific problems arising in CLIR, the solutions proposed in this area, as well as the remaining problems. The book starts with a general description of the monolingual IR and CLIR problems. Different classes of approaches to translation are then presented: approaches using an MT system, dictionary-based translation and approaches based on parallel and comparable corpora. In addition, the typical retrieval effectiveness using different approaches is compared. It will be shown that translation approaches specifically designed for CLIR can rival and outperform high-quality MT systems. Finally, the book offers a look into the future that draws a strong parallel between query expansion in monolingual IR and query translation in CLIR, suggesting that many approaches developed in monolingual IR can be adapted to CLIR. The book can be used as an introduction to CLIR. Advanced readers can also find more technical details and discussions about the remaining research challenges in the future. It is suitable to new researchers who intend to carry out research on CLIR. Table of Contents: Preface / Introduction / Using Manually Constructed Translation Systems and Resources for CLIR / Translation Based on Parallel and Comparable Corpora / Other Methods to Improve CLIR / A Look into the Future: Toward a Unified View of Monolingual IR and CLIR? / References / Author Biography

This book presents the thoroughly refereed post-proceedings of a workshop by the Cross-Language Evaluation Forum Campaign, CLEF 2002, held in Rome, Italy in September 2002. The 43 revised full papers presented together with an introduction and run data in an appendix were carefully reviewed and revised upon presentation at the workshop. The papers are organized in topical sections on systems evaluation experiments, cross language and more, monolingual experiments, mainly domain-specific information retrieval, interactive issues, cross-language spoken document retrieval, and cross-language evaluation issues and initiatives.

The second evaluation campaign of the Cross Language Evaluation Forum (CLEF) for European languages was held from January to September 2001. This campaign proved a great success, and showed an increase in participation of around 70% com pared with CLEF 2000. It culminated in a two day workshop in Darmstadt, Germany, 3–4 September, in conjunction with the 5th European Conference on Digital Libraries (ECDL 2001). On the first day of the workshop, the results of the CLEF 2001 evalua tion campaign were reported and discussed in paper and poster sessions. The second day focused on the current needs of cross language systems and how evaluation cam paigns in the future can best be designed to stimulate progress. The workshop was attended by nearly 50 researchers and system developers from both academia and in dustry. It provided an important opportunity for researchers working in the same area to get together and exchange ideas and experiences. Copies of all the presentations are available on the CLEF web site at http://www. clef campaign. org. This volume con tains thoroughly revised and expanded versions of the papers presented at the work shop and provides an exhaustive record of the CLEF 2001 campaign. CLEF 2001 was conducted as an activity of the DELOS Network of Excellence for Digital Libraries, funded by the EC Information Society Technologies program to further research in digital library technologies. The activity was organized in collabo ration with the US National Institute of Standards and Technology (NIST).

The second evaluation campaign of the Cross Language Evaluation Forum (CLEF) for European languages was held from January to September 2001. This campaign proved a great success, and showed an increase in participation of around 70% com pared with CLEF 2000. It culminated in a two day workshop in Darmstadt, Germany, 3–4 September, in conjunction with the 5th European Conference on Digital Libraries (ECDL 2001). On the first day of the workshop, the results of the CLEF 2001 evalua tion campaign were reported and discussed in paper and poster sessions. The second day focused on the current needs of cross language systems and how evaluation cam paigns in the future can best be designed to stimulate progress. The workshop was attended by nearly 50 researchers and system developers from both academia and in dustry. It provided an important opportunity for researchers working in the same area to get together and exchange ideas and experiences. Copies of all the presentations are available on the CLEF web site at http://www. clef campaign. org. This volume con tains thoroughly revised and expanded versions of the papers presented at the work shop and provides an exhaustive record of the CLEF 2001 campaign. CLEF 2001 was conducted as an activity of the DELOS Network of Excellence for Digital Libraries, funded by the EC Information Society Technologies program to further research in digital library technologies. The activity was organized in collabo ration with the US National Institute of Standards and Technology (NIST).

Most of the papers in this volume were first presented at the Workshop on Cross-Linguistic Information Retrieval that was held August 22, 1996 dur ing the SIGIR'96 Conference. Alan Smeaton of Dublin University and Paraic Sheridan of the ETH, Zurich, were the two other members of the Scientific Committee for this workshop. SIGIR is the Association for Computing Ma chinery (ACM) Special Interest Group on Information Retrieval, and they have held conferences yearly since 1977. Three additional papers have been added: Chapter 4 Distributed Cross-Lingual Information retrieval describes the EMIR retrieval system, one of the first general cross-language systems to be implemented and evaluated; Chapter 6 Mapping Vocabularies Using Latent Semantic Indexing, which originally appeared as a technical report in the Lab oratory for Computational Linguistics at Carnegie Mellon University in 1991, is included here because it was one of the earliest, though hard-to-find, publi cations showing the application of Latent Semantic Indexing to the problem of cross-language retrieval; and Chapter 10 A Weighted Boolean Model for Cross Language Text Retrieval describes a recent approach to solving the translation term weighting problem, specific to Cross-Language Information Retrieval. Gregory Grefenstette CONTRIBUTORS Lisa Ballesteros David Hull W, Bruce Croft Gregory Grefenstette Center for Intelligent Xerox Research Centre Europe Information Retrieval Grenoble Laboratory Computer Science Department University of Massachusetts Thomas K. Landauer Department of Psychology Mark W. Davis and Institute of Cognitive Science Computing Research Lab University of Colorado, Boulder New Mexico State University Michael L. Littman Bonnie J.

Evaluation has always played a major role in information retrieval, with the early pioneers such as Cyril Cleverdon and Gerard Salton laying the foundations for most of the evaluation methodologies in use today. The retrieval community has been extremely fortunate to have such a well-grounded evaluation paradigm during a period when most of the human language technologies were just developing. This lecture has the goal of explaining where these evaluation methodologies came from and how they have continued to adapt to the vastly changed environment in the search engine world today. The lecture starts with a discussion of the early evaluation of information retrieval systems, starting with the Cranfield testing in the early 1960s, continuing with the Lancaster "user" study for MEDLARS, and presenting the various test collection investigations by the SMART project and by groups in Britain. The emphasis in this chapter is on the how and the why of the various methodologies developed. The second chapter covers the more recent "batch" evaluations, examining the methodologies used in the various open evaluation campaigns such as TREC, NTCIR (emphasis on Asian languages), CLEF (emphasis on European languages), INEX (emphasis on semi-structured data), etc. Here again the focus is on the how and why, and in particular on the evolving of the older evaluation methodologies to handle new information access techniques. This includes how the test collection techniques were modified and how the metrics were changed to better reflect operational environments. The final chapters look at evaluation issues in user studies -- the interactive part of information retrieval, including a look at the search log studies mainly done by the commercial search engines. Here the goal is to show, via case studies, how the high-level issues of experimental design affect the final evaluations. Table of Contents: Introduction and Early History / "Batch" Evaluation Since 1992 / Interactive Evaluation / Conclusion