SFU Computing Science 02-3 ________________________________________________________________________ CMPT 882-3 G2" Statistical Learning of Natural Language Instructor: A. Sarkar SFU Final Exam: ________________________________________________________________________ OBJECTIVE/DESCRIPTION: How can we learn to process natural language text? How much human supervision is needed for the learning process? In this course we will study basic algorithms that produce state of the art results on tasks involving natural language text. For each of these tasks, we will compare knowledge-rich approaches which use a lot of human supervision to knowledge-poor techniques which use bootstrapping. We will predominantly look at statistical approaches to learning, comparing generative models with discriminative models. However, we will look at some non-probabilistic methods for learning as well. Note that this course will not provide a broad overview of the entire field but rather we will look at specific algorithms in depth. TOPICS: o Bootstrapping techniques in learning word meanings: word-sense disambiguation. o Hidden Markov Models (HMMs): Maximum Likelihood and the EM Algorithm. o Non-recursive analysis of language with HMMs: Part of Speech Tagging and Chunking. o Error Rate vs. Likelihood, Part I: Non-probabilistic Techniques for Learning (Transformation-Based Learning) o Hypothesis Testing: Unsupervised learning of lexical knowledge o Ambiguity resolution in parsing: Prepositional phrase attachment o Supervised learning of parsers from a Treebank o Unsupervised learning of parsers: The Inside-Outside Algorithm o Error Rate vs. Likelihood, Part II: Discriminative Techniques (Maximum-Entropy Models, Boosting) o Learning linguistically detailed grammars GRADING: Homework (30%), class participation (10%), class presentation (20%), Project and research report (40%). The project will be either a group or an individual project depending on the number of students and will involve experimental work on text corpora. TEXTBOOKS: o None. (handouts, conference, and journal papers will be distributed in class), , REFERENCES: o Foundations of Statistical Natural Language Processing, Christopher, MIT Press, 1999: Recommended to brush up on basics o Speech and Language Processing, Daniel Jurafsky and James Martin, Prentice-Hall, 2000: Recommended to brush up on basics. PREREQUISITES/COREQUISITES: A course in computational linguistics or natural language processing, such as CMPT 413, or CMPT 825. Some exposure to elementary probability theory is needed. Distributed: August 8, 2002 ....................................................................... Academic Honesty plays a key role in our efforts to maintain a high standard of academic excellence and integrity. Students are advised that ALL acts of intellectual dishonesty are subject to disciplinary action by the School; serious infractions are dealt with in accordance with the Code of Academic Honesty (T10.02) (http://www.sfu.ca/policies/teaching/t10-02.htm). Students are encouraged to read the School's Statement on Intellectual Honesty (http://www.cs.sfu.ca/undergrad/Policies/honesty.html).