Coreference and Its Applications 
Proceedings of the Workshop 
Edited by 
Amit Bagga, Breck Baldwin, and Sara Shelton 
22 June 1999 
University of Maryland 
College Park, Maryland, USA 
Published by the Association for Computational Linguistics 
©1999, Association for Computational Linguistics 
Order additional copies from: 
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PREFACE 
Coreference is in some sense nature's own hyperlink. It conveys how individual statements are 
connected within documents, across documents and across bodies of human knowledge. Conse- 
quently coreference resolution algorithms are at the core of Natural Language Processing. Most 
of the work done on coreference deals with a single language and a single text document (usually 
newswire). 
As NLP research matures into "application" phases (as opposed to theory-development), NLP 
systems are moving beyond traditional research sources to document sets which reflect a more 
natural, research-oriented mix. This shift can be seen in both the document sets and tasks used in 
recent HUB, MET, and TDT evaluations. The new sources consist of documents in several different 
languages, documents with data from noisy sources, and documents containing multimedia. In order 
for NLP systems to make a successful transition to these new sources, it is critical for coreference 
resolution systems to also work on these new sources. 
The Workshop on Coreference and Its Applications, held on June 22nd, 1999 at the University 
of Maryland, College Park, Maryland, USA, was organized around the goals of discussing, pro- 
moting, and presenting new research results (positive and negative) regarding the theory, design 
and evaluation of coreference resolution systems that deal with non-traditional data sources. In 
particular, the goal of the workshop was to focus on systems dealing with the following types of 
coreference: 
• Cross-document coreference 
• Coreference resolution in languages other than English 
• Coreference resolution on noisy data 
• Coreference resolution on non-text data (example: human speech) 
• Coreference resolution on multimedia data 
In addition, the workshop also focused on innovative NLP applications that rely heavily on coref- 
erence resolution systems. The workshop was sponsored by the Association for Computational 
Linguistics (ACL). 
We would like to thank all authors who showed their interest by submitting papers to the 
workshop. We would also like to thank the members of the program committee: Branimir Boguraev 
(IBM Research), Ed Hovy (USC Information Sciences Institute), Mark T. Maybury (MITRE), and 
Ruslan Mitkov (University of Wolverhampton). 
Amit Bagga 
Breck Baldwin 
Sara Shelton 

Workshop Program 
9:00--9:05 
9:05--9:30 
):30--9:55 
\[I Opening 
Session: Cross-Document Coreference 
Cross-Document Event Coreference: 
Annotations, Experiments, and 
Obse~ations 
Is Hillary Rodham Clinton the President? 
Disambiguating Names Across 
Documents 
lAmit Bagga and Breck Baldwin, General 
\[Electric CRD and University of 
IPennsylvania 
II Yael Ravin and Zunaid Kazi, IBM T.J. I Watson Research Center 
Session: Multimedia Coreference 
9:55--10:20 Koichi Yamada, Kazunari Sugiyama, \[\[Identification of Coreference Between 
Yasunori Yonamine and Hiroshi Nakagawa, INames and Faces 
Yokohama National University 
10:20--10:50 II Coffee Break 
10:50--11:15 \[\[Utiyama Masao and Hasida Koiti, Shinshu \[\[Automatic Slide Presentation from II 
University and Electrotechnical Laboratory \[ISemantically Annotated Documents 
I1(ETL) II 
Session: Coreference in Non-English Languages 
11" 15-- 11:40 Masaki Murata, Hitoshi Isahara and Makoto Resolution of Indirect Anaphora in 
Nagao, Communications Research IIJapanese Sentences Using Examples "X 
Laboratory, and Kyoto University Uno Y (Y OF X) 
11:40--12:05 Masaki Murata, Hitoshi Isahara and Makoto Pronoun Resolution in Japanese Sentences 
Nagao, Communications Research IIUsing Surface Expressions and Examples 
Laboratory, and Kyoto University n 
12:05-- 13" 30 Lunch Break 
13:30--13:55 
13:55--14:20 
14:20--14:45 
14:45--15:10 
Michael Paul, Kazuhide Yamamoto and 
Eiichiro Sumita, ATR Interpreting 
Telecommunications Research Laboratory 
Marco Rocha, Universidade Federal de 
Santa Catarina 
Pedro Amo, Francisco L. Ferreras, 
Fernando Cruz and Saturnino Maldonado, 
Universidad de Alcala 
Jesus Peril, Manuel Palomar and Antonio 
Ferrandez, University of Alicante 
Corpus-Based Anaphora Resolution 
Towards Antecedent Preference 
Coreference resolution in dialogues in 
English and Portuguese 
Orthographic Co-Reference Resolution 
Between Proper Nouns Through the 
Calculation of the Relation of 
"Replicancia" 
Coreference-oriented Interlingual Slot 
Structure & Machine Translation 
15:10--15:45 Coffee Break 
Session: Applications of Coreference 
15:45--16:10 Saliha Azzam, Kevin Humphreys and Using Coreference Chains for Text 
Robert Gaizauskas, University of Sheffield Summarization 
16:10--16:35 
16:35--17:00 
Thomas S. Morton, University of Using Coreference for Question 
Pennsylvania Answering 
Session: Coreference Annotation 
Kees van Deemter and Rodger Kibble, What is coreference, and what should 
University of Brighton coreference annotation be? 
Table of Contents 
Cross-Document Event Coreference: Annotations, Experiments, and Observations 
Amit Bagga and Breck Baldwin .............................................. 1 
Is Hillary Rodham Clinton the President? Disambiguating Names Across Documents 
Yael Ravin and Zunaid Kazi ................................................. 9 
Identification of Coreference Between Names and Faces 
Koichi Yamada, Kazunari Sugiyama, Yasunori Yonamine and Hiroshi Nakagawa ..... 17 
Automatic Slide Presentation from Semantically Annotated Documents 
Utiyama Masao and Hasida Koiti ............................................ 25 
Resolution of Indirect Anaphora in Japanese Sentences Using Examples "X No Y (Y 
Of X)" 
Masaki Murata, Hitoshi Isahara and Makoto Nagao ............................. 31 
Pronoun Resolution in Japanese Sentences Using Surface Expressions and Examples 
Masaki Murata, Hitoshi Isahara and Makoto Nagao ............................. 39 
Corpus-based Anaphora Resolution Towards Antecedent Preference 
Michael Paul, Kazuhide Yamamoto and Eiichiro Sumita ......................... 47 
Coreference Resolution in Dialogues in English and Portuguese 
Marco Rocha ............................................................ 53 
Orthographic Co-reference Resolution Between Proper Nouns Through the 
Calculation of the Relation of "Replicancia" 
Pedro Amo, Francisco L. Ferreras, Fernando Cruz and Saturnino Maldonado ......... 61 
Coreference-oriented Interlingual Slot Structure & Machine Translation 
Jesus Peral, Manuel Palomar and Antonio Ferrandez ............................. 69 
Using Coreference Chains for Text Summarization 
Saliha Azzam, Kevin Humphreys and Robert Gaizauskas ......................... 77 
Using Coreference for Question Answering 
Thomas S. Morton ....................................................... 85 
What Is Coreference, and What Should Coreference Annotation Be? 
Kees Van Deemter and Rodger Kibble ........................................ 90 

