Chapter 3: Basics of Language Modelling
|
|
- Norma Pope
- 5 years ago
- Views:
Transcription
1 Chapter 3: Basics of Language Modelling
2 Motivation Language Models are used in Speech Recognition Machine Translation Natural Language Generation Query completion For research and development: need a simple evaluation metric for fast turnaround times in experiments 2 2
3 Test your Language Model What s in your hometown newspaper??? 3 3
4 Test your Language Model What s in your hometown newspaper today 4 4
5 Test your Language Model It s raining cats and??? 5 5
6 Test your Language Model It s raining cats and dogs 6 6
7 Test your Language Model President Bill??? 7 7
8 Test your Language Model President Bill Gates 8 8
9 Definition Language Model A language model either: Predicts the next word w given a sequence of predecessor words h (history) P(w i hi ) P(w i w1,... wi 1) with i : position in text or Predicts the probability of a sequence of words P( w, w,... w,. w ) P( W 1 2 N 1 N ) 9 9
10 Language Model in Speech Recognition (ASR) Speech input Stream of feature vectors A Feature Extraction Search ^ W=argmax [P(A W) P(W)] [W] Acoustic Model P(A W) LanguageModel P(W) Recognised Word Sequence ^ W 10 10
11 Language Model in Machine Translation (MT) Source Sentence W F LexiconModel P(W F W E ) Search ^ W E =argmax [P(W F W E ) P(W E )] [W E ] LanguageModel P(W) E ) Recognised Word Sequence ^ W E 11 11
12 Sentence Completion Directly use of P(w h) Needs good search algorithms 12 12
13 The Markov Assumption: truncate the history Cutting history to M-1 words: Special cases: P(wi w1, w2,... wi 1) P(wi wi M 1,... wi 1) Zerogram (uniform distribution) P(wi w1, w2,... w i 1) 1 W Unigram P(w i w, w 1 2,... w i 1 ) P(w ) i Bigram Trigram P(wi w1, w2,... w i 1) P(wi wi 1) P(wi w1, w2,... wi 1) P(wi wi 2, wi 1)
14 How would you measure the quality of an LM? 14 14
15 Definition of Perplexity Let w 1, w 2, w N be an independent test corpus not used during training. Perplexity PP P( w -1/N 1, w2,... wn ) Interpretation: Normalized probability of test corpus 15 15
16 Example: Zerogram Language Model Zerogram P(wi w1, w2,... w i 1) (uniform distribution) 1 W PP W N i1 P( w 1 W 1, w 2 1/ N,... w N ) -1/N Interpretation: perplexity is the average de-facto size of vocabulary 16 16
17 Alternate Formulation Assumption: Use an M-gram language model History h i =w i-m+1 w i-1 Idea: collapse all identical histories 17 17
18 Alternate Formulation Example: M=2 Corpus: to be or not to be h 2 = to w 2 = be h 6 = to w 6 = be a calculate P( be to ) only once and scale it by
19 Alternate Formulation PP P( w N P( w i h i ) i1 exp log -1/N 1, w2,... wn ) N i1 1/ N P( w i h i ) 1/ N Use Bayes decomposition Try to get rid of product exp 1 log N N i1 P( w i h i ) 19 19
20 Alternate Formulation exp 1 log N N i1 P( w i h i ) exp N 1 logp( w i h i ) N 1 i exp 1 N( w, h)logp( w h) N, w h N(w,h): absolute frequency of sequence h,w on test corpus exp w, h f ( w, h)log P( w h) f(w,h) relative frequency of sequence h,w on test corpus 20 20
21 Alternate Formulation: Final Result PP P( w exp 1 w, h... w f N ) 1/ N ( w, h)log P( w h) Perplexity can also be calculated using conditional probabilities trained in the training corpus and relative frequencies from the test corpus
22 Alternate Formulation: Zerogram Example Zerogram (uniform distribution) P(wi w1, w2,... w i 1) 1 W PP exp w, h f ( w, h)log 1 exp log f ( w, h) W w, h P( w h) exp w, h 1 f ( w, h)log W log W * W exp 1 Identical result 22 22
23 Perplexity and Error Rate Perplexity is correlated to word error rate Power law relation Klakow + Peters in Speech Communication
24 Quality Measure: Mean Rank Definition: Let w follow h in the test text Sort all words after a given history according to p(w h) Determine position of correct word w Average over all events in the test text 24 24
25 Alternative: Average Rank Task: guess the next word Metric: Measure how many attempts it takes Source: Witten, Bell: Text Compression
26 Quality Measure: Mean Rank Measure Perplexity Mean Rank Correlation with ASR error rate Mean rank rank equally good in predicting ASR performance 26 26
27 Summary Language models predict the next word Applications: Speech Recognition Machine Translation Natural Language Generation Information retrieval Sentence Completion Perplexity: Measures quality of language model 27 27
Chapter 3: Basics of Language Modeling
Chapter 3: Basics of Language Modeling Section 3.1. Language Modeling in Automatic Speech Recognition (ASR) All graphs in this section are from the book by Schukat-Talamazzini unless indicated otherwise
More informationNatural Language Processing SoSe Language Modelling. (based on the slides of Dr. Saeedeh Momtazi)
Natural Language Processing SoSe 2015 Language Modelling Dr. Mariana Neves April 20th, 2015 (based on the slides of Dr. Saeedeh Momtazi) Outline 2 Motivation Estimation Evaluation Smoothing Outline 3 Motivation
More informationMachine Learning for natural language processing
Machine Learning for natural language processing N-grams and language models Laura Kallmeyer Heinrich-Heine-Universität Düsseldorf Summer 2016 1 / 25 Introduction Goals: Estimate the probability that a
More informationCross-Lingual Language Modeling for Automatic Speech Recogntion
GBO Presentation Cross-Lingual Language Modeling for Automatic Speech Recogntion November 14, 2003 Woosung Kim woosung@cs.jhu.edu Center for Language and Speech Processing Dept. of Computer Science The
More informationThe Noisy Channel Model and Markov Models
1/24 The Noisy Channel Model and Markov Models Mark Johnson September 3, 2014 2/24 The big ideas The story so far: machine learning classifiers learn a function that maps a data item X to a label Y handle
More informationNatural Language Processing SoSe Words and Language Model
Natural Language Processing SoSe 2016 Words and Language Model Dr. Mariana Neves May 2nd, 2016 Outline 2 Words Language Model Outline 3 Words Language Model Tokenization Separation of words in a sentence
More information{ Jurafsky & Martin Ch. 6:! 6.6 incl.
N-grams Now Simple (Unsmoothed) N-grams Smoothing { Add-one Smoothing { Backo { Deleted Interpolation Reading: { Jurafsky & Martin Ch. 6:! 6.6 incl. 1 Word-prediction Applications Augmentative Communication
More informationStatistical Methods for NLP
Statistical Methods for NLP Language Models, Graphical Models Sameer Maskey Week 13, April 13, 2010 Some slides provided by Stanley Chen and from Bishop Book Resources 1 Announcements Final Project Due,
More informationN-grams. Motivation. Simple n-grams. Smoothing. Backoff. N-grams L545. Dept. of Linguistics, Indiana University Spring / 24
L545 Dept. of Linguistics, Indiana University Spring 2013 1 / 24 Morphosyntax We just finished talking about morphology (cf. words) And pretty soon we re going to discuss syntax (cf. sentences) In between,
More informationRecap: Language models. Foundations of Natural Language Processing Lecture 4 Language Models: Evaluation and Smoothing. Two types of evaluation in NLP
Recap: Language models Foundations of atural Language Processing Lecture 4 Language Models: Evaluation and Smoothing Alex Lascarides (Slides based on those from Alex Lascarides, Sharon Goldwater and Philipp
More informationNatural Language Processing. Statistical Inference: n-grams
Natural Language Processing Statistical Inference: n-grams Updated 3/2009 Statistical Inference Statistical Inference consists of taking some data (generated in accordance with some unknown probability
More informationLecture 2: N-gram. Kai-Wei Chang University of Virginia Couse webpage:
Lecture 2: N-gram Kai-Wei Chang CS @ University of Virginia kw@kwchang.net Couse webpage: http://kwchang.net/teaching/nlp16 CS 6501: Natural Language Processing 1 This lecture Language Models What are
More informationStatistical Machine Translation
Statistical Machine Translation Marcello Federico FBK-irst Trento, Italy Galileo Galilei PhD School University of Pisa Pisa, 7-19 May 2008 Part V: Language Modeling 1 Comparing ASR and statistical MT N-gram
More informationLanguage Models. Data Science: Jordan Boyd-Graber University of Maryland SLIDES ADAPTED FROM PHILIP KOEHN
Language Models Data Science: Jordan Boyd-Graber University of Maryland SLIDES ADAPTED FROM PHILIP KOEHN Data Science: Jordan Boyd-Graber UMD Language Models 1 / 8 Language models Language models answer
More informationDT2118 Speech and Speaker Recognition
DT2118 Speech and Speaker Recognition Language Modelling Giampiero Salvi KTH/CSC/TMH giampi@kth.se VT 2015 1 / 56 Outline Introduction Formal Language Theory Stochastic Language Models (SLM) N-gram Language
More informationLanguage Modeling. Introduction to N-grams. Many Slides are adapted from slides by Dan Jurafsky
Language Modeling Introduction to N-grams Many Slides are adapted from slides by Dan Jurafsky Probabilistic Language Models Today s goal: assign a probability to a sentence Why? Machine Translation: P(high
More informationACS Introduction to NLP Lecture 2: Part of Speech (POS) Tagging
ACS Introduction to NLP Lecture 2: Part of Speech (POS) Tagging Stephen Clark Natural Language and Information Processing (NLIP) Group sc609@cam.ac.uk The POS Tagging Problem 2 England NNP s POS fencers
More informationProbabilistic Language Modeling
Predicting String Probabilities Probabilistic Language Modeling Which string is more likely? (Which string is more grammatical?) Grill doctoral candidates. Regina Barzilay EECS Department MIT November
More informationLanguage Modeling. Introduction to N-grams. Many Slides are adapted from slides by Dan Jurafsky
Language Modeling Introduction to N-grams Many Slides are adapted from slides by Dan Jurafsky Probabilistic Language Models Today s goal: assign a probability to a sentence Why? Machine Translation: P(high
More informationLanguage Models. Philipp Koehn. 11 September 2018
Language Models Philipp Koehn 11 September 2018 Language models 1 Language models answer the question: How likely is a string of English words good English? Help with reordering p LM (the house is small)
More informationN-gram N-gram Language Model for Large-Vocabulary Continuous Speech Recognition
2010 11 5 N-gram N-gram Language Model for Large-Vocabulary Continuous Speech Recognition 1 48-106413 Abstract Large-Vocabulary Continuous Speech Recognition(LVCSR) system has rapidly been growing today.
More informationNgram Review. CS 136 Lecture 10 Language Modeling. Thanks to Dan Jurafsky for these slides. October13, 2017 Professor Meteer
+ Ngram Review October13, 2017 Professor Meteer CS 136 Lecture 10 Language Modeling Thanks to Dan Jurafsky for these slides + ASR components n Feature Extraction, MFCCs, start of Acoustic n HMMs, the Forward
More informationSparse vectors recap. ANLP Lecture 22 Lexical Semantics with Dense Vectors. Before density, another approach to normalisation.
ANLP Lecture 22 Lexical Semantics with Dense Vectors Henry S. Thompson Based on slides by Jurafsky & Martin, some via Dorota Glowacka 5 November 2018 Previous lectures: Sparse vectors recap How to represent
More informationANLP Lecture 22 Lexical Semantics with Dense Vectors
ANLP Lecture 22 Lexical Semantics with Dense Vectors Henry S. Thompson Based on slides by Jurafsky & Martin, some via Dorota Glowacka 5 November 2018 Henry S. Thompson ANLP Lecture 22 5 November 2018 Previous
More informationSpeech Recognition Lecture 5: N-gram Language Models. Eugene Weinstein Google, NYU Courant Institute Slide Credit: Mehryar Mohri
Speech Recognition Lecture 5: N-gram Language Models Eugene Weinstein Google, NYU Courant Institute eugenew@cs.nyu.edu Slide Credit: Mehryar Mohri Components Acoustic and pronunciation model: Pr(o w) =
More informationLanguage Modeling. Michael Collins, Columbia University
Language Modeling Michael Collins, Columbia University Overview The language modeling problem Trigram models Evaluating language models: perplexity Estimation techniques: Linear interpolation Discounting
More informationperplexity = 2 cross-entropy (5.1) cross-entropy = 1 N log 2 likelihood (5.2) likelihood = P(w 1 w N ) (5.3)
Chapter 5 Language Modeling 5.1 Introduction A language model is simply a model of what strings (of words) are more or less likely to be generated by a speaker of English (or some other language). More
More informationN-gram Language Modeling
N-gram Language Modeling Outline: Statistical Language Model (LM) Intro General N-gram models Basic (non-parametric) n-grams Class LMs Mixtures Part I: Statistical Language Model (LM) Intro What is a statistical
More informationTnT Part of Speech Tagger
TnT Part of Speech Tagger By Thorsten Brants Presented By Arghya Roy Chaudhuri Kevin Patel Satyam July 29, 2014 1 / 31 Outline 1 Why Then? Why Now? 2 Underlying Model Other technicalities 3 Evaluation
More informationN-gram Language Modeling Tutorial
N-gram Language Modeling Tutorial Dustin Hillard and Sarah Petersen Lecture notes courtesy of Prof. Mari Ostendorf Outline: Statistical Language Model (LM) Basics n-gram models Class LMs Cache LMs Mixtures
More informationConditional Language Modeling. Chris Dyer
Conditional Language Modeling Chris Dyer Unconditional LMs A language model assigns probabilities to sequences of words,. w =(w 1,w 2,...,w`) It is convenient to decompose this probability using the chain
More informationNatural Language Processing
Natural Language Processing Language models Based on slides from Michael Collins, Chris Manning and Richard Soccer Plan Problem definition Trigram models Evaluation Estimation Interpolation Discounting
More informationLanguage Models. CS6200: Information Retrieval. Slides by: Jesse Anderton
Language Models CS6200: Information Retrieval Slides by: Jesse Anderton What s wrong with VSMs? Vector Space Models work reasonably well, but have a few problems: They are based on bag-of-words, so they
More informationEmpirical Methods in Natural Language Processing Lecture 5 N-gram Language Models
Empirical Methods in Natural Language Processing Lecture 5 N-gram Language Models (most slides from Sharon Goldwater; some adapted from Alex Lascarides) 29 January 2017 Nathan Schneider ENLP Lecture 5
More informationGraphical Models. Mark Gales. Lent Machine Learning for Language Processing: Lecture 3. MPhil in Advanced Computer Science
Graphical Models Mark Gales Lent 2011 Machine Learning for Language Processing: Lecture 3 MPhil in Advanced Computer Science MPhil in Advanced Computer Science Graphical Models Graphical models have their
More informationN-gram Language Model. Language Models. Outline. Language Model Evaluation. Given a text w = w 1...,w t,...,w w we can compute its probability by:
N-gram Language Model 2 Given a text w = w 1...,w t,...,w w we can compute its probability by: Language Models Marcello Federico FBK-irst Trento, Italy 2016 w Y Pr(w) =Pr(w 1 ) Pr(w t h t ) (1) t=2 where
More informationCSA4050: Advanced Topics Natural Language Processing. Lecture Statistics III. Statistical Approaches to NLP
University of Malta BSc IT (Hons)Year IV CSA4050: Advanced Topics Natural Language Processing Lecture Statistics III Statistical Approaches to NLP Witten-Bell Discounting Unigrams Bigrams Dept Computer
More informationNLP: N-Grams. Dan Garrette December 27, Predictive text (text messaging clients, search engines, etc)
NLP: N-Grams Dan Garrette dhg@cs.utexas.edu December 27, 2013 1 Language Modeling Tasks Language idenfication / Authorship identification Machine Translation Speech recognition Optical character recognition
More informationBayesian Learning. Examples. Conditional Probability. Two Roles for Bayesian Methods. Prior Probability and Random Variables. The Chain Rule P (B)
Examples My mood can take 2 possible values: happy, sad. The weather can take 3 possible vales: sunny, rainy, cloudy My friends know me pretty well and say that: P(Mood=happy Weather=rainy) = 0.25 P(Mood=happy
More informationNatural Language Processing (CSE 490U): Language Models
Natural Language Processing (CSE 490U): Language Models Noah Smith c 2017 University of Washington nasmith@cs.washington.edu January 6 9, 2017 1 / 67 Very Quick Review of Probability Event space (e.g.,
More informationLanguage Modelling. Marcello Federico FBK-irst Trento, Italy. MT Marathon, Edinburgh, M. Federico SLM MT Marathon, Edinburgh, 2012
Language Modelling Marcello Federico FBK-irst Trento, Italy MT Marathon, Edinburgh, 2012 Outline 1 Role of LM in ASR and MT N-gram Language Models Evaluation of Language Models Smoothing Schemes Discounting
More informationA fast and simple algorithm for training neural probabilistic language models
A fast and simple algorithm for training neural probabilistic language models Andriy Mnih Joint work with Yee Whye Teh Gatsby Computational Neuroscience Unit University College London 25 January 2013 1
More informationAn Algorithm for Fast Calculation of Back-off N-gram Probabilities with Unigram Rescaling
An Algorithm for Fast Calculation of Back-off N-gram Probabilities with Unigram Rescaling Masaharu Kato, Tetsuo Kosaka, Akinori Ito and Shozo Makino Abstract Topic-based stochastic models such as the probabilistic
More informationLanguage Model. Introduction to N-grams
Language Model Introduction to N-grams Probabilistic Language Model Goal: assign a probability to a sentence Application: Machine Translation P(high winds tonight) > P(large winds tonight) Spelling Correction
More informationACS Introduction to NLP Lecture 3: Language Modelling and Smoothing
ACS Introduction to NLP Lecture 3: Language Modelling and Smoothing Stephen Clark Natural Language and Information Processing (NLIP) Group sc609@cam.ac.uk Language Modelling 2 A language model is a probability
More informationCMPT-825 Natural Language Processing
CMPT-825 Natural Language Processing Anoop Sarkar http://www.cs.sfu.ca/ anoop February 27, 2008 1 / 30 Cross-Entropy and Perplexity Smoothing n-gram Models Add-one Smoothing Additive Smoothing Good-Turing
More informationAdvanced topics in language modeling: MaxEnt, features and marginal distritubion constraints
Advanced topics in language modeling: MaxEnt, features and marginal distritubion constraints Brian Roark, Google NYU CSCI-GA.2585 Speech Recognition, Weds., April 15, 2015 (Don t forget to pay your taxes!)
More informationThe Language Modeling Problem (Fall 2007) Smoothed Estimation, and Language Modeling. The Language Modeling Problem (Continued) Overview
The Language Modeling Problem We have some (finite) vocabulary, say V = {the, a, man, telescope, Beckham, two, } 6.864 (Fall 2007) Smoothed Estimation, and Language Modeling We have an (infinite) set of
More informationWeek 13: Language Modeling II Smoothing in Language Modeling. Irina Sergienya
Week 13: Language Modeling II Smoothing in Language Modeling Irina Sergienya 07.07.2015 Couple of words first... There are much more smoothing techniques, [e.g. Katz back-off, Jelinek-Mercer,...] and techniques
More informationLanguage Technology. Unit 1: Sequence Models. CUNY Graduate Center Spring Lectures 5-6: Language Models and Smoothing. required hard optional
Language Technology CUNY Graduate Center Spring 2013 Unit 1: Sequence Models Lectures 5-6: Language Models and Smoothing required hard optional Professor Liang Huang liang.huang.sh@gmail.com Python Review:
More informationSYNTHER A NEW M-GRAM POS TAGGER
SYNTHER A NEW M-GRAM POS TAGGER David Sündermann and Hermann Ney RWTH Aachen University of Technology, Computer Science Department Ahornstr. 55, 52056 Aachen, Germany {suendermann,ney}@cs.rwth-aachen.de
More informationFoundations of Natural Language Processing Lecture 5 More smoothing and the Noisy Channel Model
Foundations of Natural Language Processing Lecture 5 More smoothing and the Noisy Channel Model Alex Lascarides (Slides based on those from Alex Lascarides, Sharon Goldwater and Philipop Koehn) 30 January
More informationLanguage Processing with Perl and Prolog
Language Processing with Perl and Prolog Chapter 5: Counting Words Pierre Nugues Lund University Pierre.Nugues@cs.lth.se http://cs.lth.se/pierre_nugues/ Pierre Nugues Language Processing with Perl and
More informationLanguage Models. Hongning Wang
Language Models Hongning Wang CS@UVa Notion of Relevance Relevance (Rep(q), Rep(d)) Similarity P(r1 q,d) r {0,1} Probability of Relevance P(d q) or P(q d) Probabilistic inference Different rep & similarity
More informationEmpirical Methods in Natural Language Processing Lecture 10a More smoothing and the Noisy Channel Model
Empirical Methods in Natural Language Processing Lecture 10a More smoothing and the Noisy Channel Model (most slides from Sharon Goldwater; some adapted from Philipp Koehn) 5 October 2016 Nathan Schneider
More informationUniversität Potsdam Institut für Informatik Lehrstuhl Maschinelles Lernen. Language Models. Tobias Scheffer
Universität Potsdam Institut für Informatik Lehrstuhl Maschinelles Lernen Language Models Tobias Scheffer Stochastic Language Models A stochastic language model is a probability distribution over words.
More informationLearning to translate with neural networks. Michael Auli
Learning to translate with neural networks Michael Auli 1 Neural networks for text processing Similar words near each other France Spain dog cat Neural networks for text processing Similar words near each
More informationCS 6120/CS4120: Natural Language Processing
CS 6120/CS4120: Natural Language Processing Instructor: Prof. Lu Wang College of Computer and Information Science Northeastern University Webpage: www.ccs.neu.edu/home/luwang Outline Probabilistic language
More informationCS4705. Probability Review and Naïve Bayes. Slides from Dragomir Radev
CS4705 Probability Review and Naïve Bayes Slides from Dragomir Radev Classification using a Generative Approach Previously on NLP discriminative models P C D here is a line with all the social media posts
More informationAlgorithms for NLP. Language Modeling III. Taylor Berg-Kirkpatrick CMU Slides: Dan Klein UC Berkeley
Algorithms for NLP Language Modeling III Taylor Berg-Kirkpatrick CMU Slides: Dan Klein UC Berkeley Announcements Office hours on website but no OH for Taylor until next week. Efficient Hashing Closed address
More informationDoctoral Course in Speech Recognition. May 2007 Kjell Elenius
Doctoral Course in Speech Recognition May 2007 Kjell Elenius CHAPTER 12 BASIC SEARCH ALGORITHMS State-based search paradigm Triplet S, O, G S, set of initial states O, set of operators applied on a state
More informationSparse Models for Speech Recognition
Sparse Models for Speech Recognition Weibin Zhang and Pascale Fung Human Language Technology Center Hong Kong University of Science and Technology Outline Introduction to speech recognition Motivations
More informationVariational Decoding for Statistical Machine Translation
Variational Decoding for Statistical Machine Translation Zhifei Li, Jason Eisner, and Sanjeev Khudanpur Center for Language and Speech Processing Computer Science Department Johns Hopkins University 1
More informationExploring Asymmetric Clustering for Statistical Language Modeling
Proceedings of the 40th Annual Meeting of the Association for Computational Linguistics (ACL, Philadelphia, July 2002, pp. 83-90. Exploring Asymmetric Clustering for Statistical Language Modeling Jianfeng
More informationCS230: Lecture 10 Sequence models II
CS23: Lecture 1 Sequence models II Today s outline We will learn how to: - Automatically score an NLP model I. BLEU score - Improve Machine II. Beam Search Translation results with Beam search III. Speech
More informationCSC321 Lecture 7 Neural language models
CSC321 Lecture 7 Neural language models Roger Grosse and Nitish Srivastava February 1, 2015 Roger Grosse and Nitish Srivastava CSC321 Lecture 7 Neural language models February 1, 2015 1 / 19 Overview We
More informationSequences and Information
Sequences and Information Rahul Siddharthan The Institute of Mathematical Sciences, Chennai, India http://www.imsc.res.in/ rsidd/ Facets 16, 04/07/2016 This box says something By looking at the symbols
More informationIntroduction to N-grams
Lecture Notes, Artificial Intelligence Course, University of Birzeit, Palestine Spring Semester, 2014 (Advanced/) Artificial Intelligence Probabilistic Language Modeling Introduction to N-grams Dr. Mustafa
More informationKneser-Ney smoothing explained
foldl home blog contact feed Kneser-Ney smoothing explained 18 January 2014 Language models are an essential element of natural language processing, central to tasks ranging from spellchecking to machine
More informationStatistical Phrase-Based Speech Translation
Statistical Phrase-Based Speech Translation Lambert Mathias 1 William Byrne 2 1 Center for Language and Speech Processing Department of Electrical and Computer Engineering Johns Hopkins University 2 Machine
More informationStatistical methods in NLP, lecture 7 Tagging and parsing
Statistical methods in NLP, lecture 7 Tagging and parsing Richard Johansson February 25, 2014 overview of today's lecture HMM tagging recap assignment 3 PCFG recap dependency parsing VG assignment 1 overview
More informationMachine Learning for natural language processing
Machine Learning for natural language processing Classification: Naive Bayes Laura Kallmeyer Heinrich-Heine-Universität Düsseldorf Summer 2016 1 / 20 Introduction Classification = supervised method for
More informationTopic Modeling: Beyond Bag-of-Words
University of Cambridge hmw26@cam.ac.uk June 26, 2006 Generative Probabilistic Models of Text Used in text compression, predictive text entry, information retrieval Estimate probability of a word in a
More informationLog-linear models (part 1)
Log-linear models (part 1) CS 690N, Spring 2018 Advanced Natural Language Processing http://people.cs.umass.edu/~brenocon/anlp2018/ Brendan O Connor College of Information and Computer Sciences University
More informationMidterm sample questions
Midterm sample questions CS 585, Brendan O Connor and David Belanger October 12, 2014 1 Topics on the midterm Language concepts Translation issues: word order, multiword translations Human evaluation Parts
More informationLecture 5 Neural models for NLP
CS546: Machine Learning in NLP (Spring 2018) http://courses.engr.illinois.edu/cs546/ Lecture 5 Neural models for NLP Julia Hockenmaier juliahmr@illinois.edu 3324 Siebel Center Office hours: Tue/Thu 2pm-3pm
More informationIN FALL NATURAL LANGUAGE PROCESSING. Jan Tore Lønning
1 IN4080 2018 FALL NATURAL LANGUAGE PROCESSING Jan Tore Lønning 2 Logistic regression Lecture 8, 26 Sept Today 3 Recap: HMM-tagging Generative and discriminative classifiers Linear classifiers Logistic
More informationRanked Retrieval (2)
Text Technologies for Data Science INFR11145 Ranked Retrieval (2) Instructor: Walid Magdy 31-Oct-2017 Lecture Objectives Learn about Probabilistic models BM25 Learn about LM for IR 2 1 Recall: VSM & TFIDF
More informationLecture 3: ASR: HMMs, Forward, Viterbi
Original slides by Dan Jurafsky CS 224S / LINGUIST 285 Spoken Language Processing Andrew Maas Stanford University Spring 2017 Lecture 3: ASR: HMMs, Forward, Viterbi Fun informative read on phonetics The
More informationDeep Learning Basics Lecture 10: Neural Language Models. Princeton University COS 495 Instructor: Yingyu Liang
Deep Learning Basics Lecture 10: Neural Language Models Princeton University COS 495 Instructor: Yingyu Liang Natural language Processing (NLP) The processing of the human languages by computers One of
More informationHierarchical Bayesian Nonparametric Models of Language and Text
Hierarchical Bayesian Nonparametric Models of Language and Text Gatsby Computational Neuroscience Unit, UCL Joint work with Frank Wood *, Jan Gasthaus *, Cedric Archambeau, Lancelot James SIGIR Workshop
More informationCSCI 5832 Natural Language Processing. Today 2/19. Statistical Sequence Classification. Lecture 9
CSCI 5832 Natural Language Processing Jim Martin Lecture 9 1 Today 2/19 Review HMMs for POS tagging Entropy intuition Statistical Sequence classifiers HMMs MaxEnt MEMMs 2 Statistical Sequence Classification
More informationLecture 9: Hidden Markov Model
Lecture 9: Hidden Markov Model Kai-Wei Chang CS @ University of Virginia kw@kwchang.net Couse webpage: http://kwchang.net/teaching/nlp16 CS6501 Natural Language Processing 1 This lecture v Hidden Markov
More informationDeep Learning Sequence to Sequence models: Attention Models. 17 March 2018
Deep Learning Sequence to Sequence models: Attention Models 17 March 2018 1 Sequence-to-sequence modelling Problem: E.g. A sequence X 1 X N goes in A different sequence Y 1 Y M comes out Speech recognition:
More informationThe Noisy Channel Model. CS 294-5: Statistical Natural Language Processing. Speech Recognition Architecture. Digitizing Speech
CS 294-5: Statistical Natural Language Processing The Noisy Channel Model Speech Recognition II Lecture 21: 11/29/05 Search through space of all possible sentences. Pick the one that is most probable given
More informationFun with weighted FSTs
Fun with weighted FSTs Informatics 2A: Lecture 18 Shay Cohen School of Informatics University of Edinburgh 29 October 2018 1 / 35 Kedzie et al. (2018) - Content Selection in Deep Learning Models of Summarization
More informationLanguage Modelling: Smoothing and Model Complexity. COMP-599 Sept 14, 2016
Language Modelling: Smoothing and Model Complexity COMP-599 Sept 14, 2016 Announcements A1 has been released Due on Wednesday, September 28th Start code for Question 4: Includes some of the package import
More informationGrammars and introduction to machine learning. Computers Playing Jeopardy! Course Stony Brook University
Grammars and introduction to machine learning Computers Playing Jeopardy! Course Stony Brook University Last class: grammars and parsing in Prolog Noun -> roller Verb thrills VP Verb NP S NP VP NP S VP
More informationHidden Markov Models. x 1 x 2 x 3 x N
Hidden Markov Models 1 1 1 1 K K K K x 1 x x 3 x N Example: The dishonest casino A casino has two dice: Fair die P(1) = P() = P(3) = P(4) = P(5) = P(6) = 1/6 Loaded die P(1) = P() = P(3) = P(4) = P(5)
More informationNaïve Bayes, Maxent and Neural Models
Naïve Bayes, Maxent and Neural Models CMSC 473/673 UMBC Some slides adapted from 3SLP Outline Recap: classification (MAP vs. noisy channel) & evaluation Naïve Bayes (NB) classification Terminology: bag-of-words
More informationHidden Markov Modelling
Hidden Markov Modelling Introduction Problem formulation Forward-Backward algorithm Viterbi search Baum-Welch parameter estimation Other considerations Multiple observation sequences Phone-based models
More informationSpeech Translation: from Singlebest to N-Best to Lattice Translation. Spoken Language Communication Laboratories
Speech Translation: from Singlebest to N-Best to Lattice Translation Ruiqiang ZHANG Genichiro KIKUI Spoken Language Communication Laboratories 2 Speech Translation Structure Single-best only ASR Single-best
More informationStatistical methods for NLP Estimation
Statistical methods for NLP Estimation UNIVERSITY OF Richard Johansson January 29, 2015 why does the teacher care so much about the coin-tossing experiment? because it can model many situations: I pick
More information(today we are assuming sentence segmentation) Wednesday, September 10, 14
(today we are assuming sentence segmentation) 1 Your TA: David Belanger http://people.cs.umass.edu/~belanger/ I am a third year PhD student advised by Professor Andrew McCallum. Before that, I was an Associate
More informationFrom perceptrons to word embeddings. Simon Šuster University of Groningen
From perceptrons to word embeddings Simon Šuster University of Groningen Outline A basic computational unit Weighting some input to produce an output: classification Perceptron Classify tweets Written
More informationWhat to Expect from Expected Kneser-Ney Smoothing
What to Expect from Expected Kneser-Ney Smoothing Michael Levit, Sarangarajan Parthasarathy, Shuangyu Chang Microsoft, USA {mlevit sarangp shchang}@microsoft.com Abstract Kneser-Ney smoothing on expected
More informationLanguage Modelling. Steve Renals. Automatic Speech Recognition ASR Lecture 11 6 March ASR Lecture 11 Language Modelling 1
Language Modelling Steve Renals Automatic Speech Recognition ASR Lecture 11 6 March 2017 ASR Lecture 11 Language Modelling 1 HMM Speech Recognition Recorded Speech Decoded Text (Transcription) Acoustic
More informationRecurrent Neural Networks (Part - 2) Sumit Chopra Facebook
Recurrent Neural Networks (Part - 2) Sumit Chopra Facebook Recap Standard RNNs Training: Backpropagation Through Time (BPTT) Application to sequence modeling Language modeling Applications: Automatic speech
More informationANLP Lecture 6 N-gram models and smoothing
ANLP Lecture 6 N-gram models and smoothing Sharon Goldwater (some slides from Philipp Koehn) 27 September 2018 Sharon Goldwater ANLP Lecture 6 27 September 2018 Recap: N-gram models We can model sentence
More informationTopics in Natural Language Processing
Topics in Natural Language Processing Shay Cohen Institute for Language, Cognition and Computation University of Edinburgh Lecture 9 Administrativia Next class will be a summary Please email me questions
More information