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CS224N Section 3: Project,Corpora
Shrey Gupta January 28, 2011 (Thanks to Bill MacCartney, Helen Kwong and Pi-Chuan Chang for these materials)
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Agenda Go through administrative details regarding the final project
Presentations by research groups Resources for final project
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Final Project Proposal due in 2 weeks – Wed. 2/9 Other details
Please read the final project guide Projects from previous years: Proposal - Intended as a sanity check and to make sure that the topic is relevant to the course. 34% of your grade Team size: 1-3 member(s) Reports and code due on 3/9(late days allowed) Project presentations on 3/17
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Project Ideas Topics from Syllabus Ideas listed in the project guide
Papers from NLP conferences - Collaboration with research groups at Stanford Something you are really interested in !
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Presentations by research groups
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Topics Relation Extraction in the Knowledge Base Population (KBP) context BioNLP Event Extraction Predicting U.S. Elections with Twitter Litigation Analysis - Outcome Prediction, Field Classification, Attorney Recommendation, Entity Resolution Document classification to identify outbreak-related web content
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Resources
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Corpora Corpora@Stanford LDC (Linguistic Data Consortium)
Some are on AFS (/afs/ir/data/linguistic-data/); some are available on DVD/CDs in the linguistic department LDC (Linguistic Data Consortium) Links to many resources
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Treebanks Most widely used: Penn Treebank
There's PTB2 and PTB3. Use PTB3, i.e. Treebank-3 Contains: 50,000 sentences (1,000,000 words) of WSJ text from 1989 30,000 sentences (400,000 words) of Brown corpus Parsed WSJ trees: /afs/ir/data/linguistic-data/Treebank/3/parsed/mrg/wsj/ BLLIP: like PTB, WSJ text, but 30m words, parsed automatically by Charniak Switchboard: telephone conversations PTB WSJ contains sections 0 through 24, ~2400 sentences each, but section 24 is half size. ~50,000 sentences total. Convention in parsing world: sections 2-21: training (39,832 sentences) section 0 or 22 or 24: development testing section 23: final test data Sections 0 and 1 perceived to be less reliable -- annotators warming up. PTB3 adds some new stuff vs. PTB2, but NO BUG FIXES.
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Parsed corpora in other languages
Penn Arabic Treebank Corpus 734 stories (140,000 words) Penn Chinese Treebank Corpus 50,000 sentences German (newspaper text): NEGRA TIGER Tueba-D/Z
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Part-of-speech tagged corpora
POS tags from treebanks British National Corpus (BNC) 100m words wide sample of British English: newspapers, books, letters
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Named Entity Recognition (NER)
Message Understanding Conference (MUC) We have MUC-6 and MUC-7 Example: /afs/ir/data/linguistic-data/MUC_7/muc_7/data/training.ne.eng.keys CoNLL shared tasks: Language-Independent Named Entity Recognition (I), (II) 2002: 2003:
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Anaphora resolution Data: MUC-6 and MUC-7
Example: Pam went home because she felt sick Demo: Unsolved problem Harder example: We gave the bananas to the monkeys because they were hungry We gave the bananas to the monkeys because they were ripe.
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Semantics WordNet Website: http://wordnet.princeton.edu/
Browse online: 150,000 nouns, verbs, adjectives, adverbs Groups words into “synsets” with short, general definitions, and records various relations between synsets, e.g. hypernym (kind-of) hierarchy. Neat visual interface: Problems with WordNet: fine-grained senses sense ordering sometimes funny (see "airline")
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Semantic Role Labeling
Detection of semantic arguments associated with each verb in a sentence Example: “I [agent] sold you [patient] a book [theme]” CoNLL shared task 2004, 2005 PropBank Adds predicate-argument relations to PTB syntax trees FrameNet: Demo from UIUC:
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More corpora for specific tasks
Word Sense Disambiguation (WSD) Senseval: Question Answering e.g. "What film introduced Jar Jar Binks?" TREC competition, Question Answering track Textual Entailment Recognizing Textual Entailment (RTE) challenges Events, temporal relations TimeBank corpus:
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More corpora for specific tasks
Topic Detection and Tracking Given documents, separate into different topics
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Speech & Dialogue Speech Dialogue BNC: 10m words Switchboard corpus
Conversations of two speakers recorded over the phone Transcriptions of their speech, with speakers labeled Example:
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Email/Spam Enron corpus TREC Spam track
/afs/ir/data/linguistic-data/Enron- -Corpus/maildir/skilling-j/ Annotated subsets(for NER): TREC Spam track
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Tools Many links to tools on the StatNLP page Parsers POS taggers
Parsers Stanford Parser (English, Chinese, German and Arabic) Online parser: Collin’s parser, Charniak’s parser, MiniPar, etc. POS taggers Named entity recognizers Language modeling toolkits
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Machine learning tools
Stanford classifier conditional loglinear (aka maximum entropy) model Weka Java library containing (nearly) every machine learning algorithm -Naive Bayes, perceptron, decision tree, MaxEnt, SVM, etc. Mallet Java; useful for statistical NLP, document classification, clustering, topic modeling, information extraction…
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Thank You ! Any questions ?
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