Citation Extractor

Nguyen BachSue Ann HongBen Lambert

AuthorOf(Author, Paper)PublishedAt(Paper, Conference)IsPaper, IsAuthor, IsConference

Extraction Task

• “Citation” = <Paper, Authors, Conference>• “Pattern”

– regular expression

Method Outline

Query Search(WIT)

Extract Patternsusing known citations

Web pages(HTML, text)

Page-specificPatterns

Citation DB

Seed (e.g. 5 citations)

Extract Citations using new patternsCitations

Query: "multiple-goal recognition from low-level signals " " Xiaoyong Chai" " Qiang Yang" "AAAI 2005 "

Page: http://www.informatik.uni-trier.de/~ley/db/indices/a-tree/y/Yang:Qiang.html

AUTHOR,AUTHOR: TITLE CONF.

4 Patterns:

AUTHOR, (A-Za-z): (A-Za-z). (A-Za-z)

(A-Za-z), AUTHOR : (A-Za-z). (A-Za-z)

(A-Za-z), (A-Za-z): TITLE. (A-Za-z)

(A-Za-z), (A-Za-z): (A-Za-z). CONF

AUTHOR, (A-Za-z): (A-Za-z). (A-Za-z)

(A-Za-z), AUTHOR : (A-Za-z). (A-Za-z)

(A-Za-z), (A-Za-z): TITLE. (A-Za-z)

(A-Za-z), (A-Za-z): (A-Za-z). CONF

Finding New Citations

AUTHOR,

AUTHOR:

TITLE CONF

.

AUTHOR,

AUTHOR,AUTHOR,

AUTHOR,

AUTHOR,

CONFCONF

AUTHOR,

AUTHOR:

AUTHOR:

System Spits Out…• 6 seeds 60 citations

• 36 of these (partial citations)– "Theory and Algorithms for Plan Merging " , " Ming Li"– "The Expected Value of Hierarchical Problem-Solving " , "

Fahiem Bacchus"– "Handling feature interactions in process-planning "

• 14 of these (partial strings)– "On D " – "On t " , " John Tromp", " Elizabeth Sweedyk", " Umest Vazirani"– "An L " , " Ronan Sleep"– "To D “

• No new conferences (end-token)

Bootstrapping, Short-Lived

• Highly restrictive regex’s– No recovery– More seeds and variety the better

• Stupid Little Things– Mis-capitalization – Variations in titles (‘-’ vs. ‘ ’)– Etc, etc, etc…

Extensions ~ Improvements• Less strict string matching

– Not case and punctuation sensitive• Better boundary detection

– Start/end tokens, HTML wrapper detection?• Better pattern construction

– e.g. n authors not 2• NER

– help find the right "window“– A source of ENTITY marker

• Use like ‘AUTHOR’, ‘TITLE’, ‘CONF’ but with probabilities/confidence values

• Evaluation with DBLP?

NER• Baseline model (News corpus)<ENAMEX_TYPE="PERSON"> M. Woszczyna, N. Aoki-Waibel, F. D. Buo, N. Coccaro, K.

Horiguchi, T. Kemp, A. Lavie, A. McNair, T. Polzin, I. Rogina, C. P. Rose, T. Schultz, B. Suhm, M. Tomita, A. Waibel, 1994, JANUS 93: </ENAMEX> Towards Spontaneous Speech Translation, Proceedings of the International Conference on Acoustics, Speech, and Signal Processing.

<ENAMEX_TYPE="PERSON"> S. Awodey. </ENAMEX> Topological Representation of the Lambda Calculus. September <ENAMEX_TYPE="PERSON"> 1998. Math. Struct. </ENAMEX> in <ENAMEX_TYPE="LOCATION"> Comp. Sci. (2000), vol. 10, pp. 81--96. </ENAMEX>

• Adapted model (News + citation corpus)<ENAMEX_TYPE="PERSON"> M. Woszczyna, N. Aoki-Waibel, F. D. Buo, N. Coccaro, K.

Horiguchi, T. Kemp, A. Lavie, A. McNair, T. Polzin, I. Rogina, C. P. Rose, T. Schultz, B. Suhm, M. Tomita, A. Waibel, 1994, JANUS 93: </ENAMEX> Towards Spontaneous Speech Translation, Proceedings of the <ENAMEX_TYPE="ORGANIZATION"> International Conference on Acoustics, Speech, </ENAMEX> and Signal Processing.

<ENAMEX_TYPE="PERSON"> L. Birkedal. </ENAMEX> A General Notion of Realizability. December 1999. Proceedings of <ENAMEX_TYPE="ORGANIZATION"> LICS 2000 </ENAMEX>

Lessons LearnedAnother Boring Text Slide

• Semi-structured text is surprisingly difficult to read

• Off-line training for wrappers and/or NER may help

• Need very high-confidence rules to ensure precision

• A continuously-running system needs robustness (internet/Google-failure, unexpected errors, …)