Course

Natural Language Processing

Indian Institute of Technology Bombay

This course on Natural Language Processing (NLP) covers a comprehensive outline of topics essential for understanding and implementing NLP techniques.

The course is divided into several key areas:

  • Sound: Biology of Speech Processing; Place and Manner of Articulation; Word Boundary Detection; Argmax based computations; HMM and Speech Recognition.
  • Words and Word Forms: Morphology fundamentals; Morphological Diversity of Indian Languages; Morphology Paradigms; Finite State Machine Based Morphology; Automatic Morphology Learning; Shallow Parsing; Named Entities; Maximum Entropy Models; Random Fields.
  • Structures: Theories of Parsing; Parsing Algorithms; Robust and Scalable Parsing on Noisy Text; Hybrid of Rule Based and Probabilistic Parsing; Scope Ambiguity and Attachment Ambiguity resolution.
  • Meaning: Lexical Knowledge Networks; Wordnet Theory; Indian Language Wordnets; Semantic Roles; Word Sense Disambiguation; Metaphors; Coreferences.
  • Web 2.0 Applications: Sentiment Analysis; Text Entailment; Machine Translation; Question Answering; Cross Lingual Information Retrieval (CLIR).

Lecture topics include:

  1. Introduction
  2. Machine Learning and NLP
  3. ArgMax Computation
  4. WordNet and its applications
  5. Parsing Algorithms and Techniques
  6. HMM, Viterbi Algorithm, and their applications in NLP
  7. Sentiment Analysis and Machine Translation tools
  8. Word Sense Disambiguation techniques
  9. Parsing Ambiguous Sentences
  10. Probabilistic Parsing Algorithms

This course is designed for individuals interested in enhancing their knowledge and skills in NLP and its practical applications.

Course Lectures
  • Mod-01 Lec-01 Introduction
    Prof. Pushpak Bhattacharyya

    This module introduces the fundamental concepts of Natural Language Processing (NLP) and its significance in artificial intelligence. Students will explore:

    • The definition and scope of NLP.
    • Real-world applications of NLP in various domains.
    • The interdisciplinary nature of NLP, combining linguistics, computer science, and statistics.
    • Challenges faced in processing natural language data.

    By the end of this module, learners will have a solid understanding of NLP's foundational principles and its relevance in today's technology-driven world.

  • Mod-01 Lec-02 Stages of NLP
    Prof. Pushpak Bhattacharyya

    This module delves into the various stages of NLP, highlighting the processes involved in transforming raw text into meaningful data. Key topics include:

    1. Tokenization and segmentation.
    2. Part-of-speech tagging and parsing.
    3. Named entity recognition.
    4. Semantic analysis.

    Students will gain insights into the methodologies employed at each stage and understand how these contribute to the overall NLP pipeline.

  • Mod-01 Lec-03 Stages of NLP Continued
    Prof. Pushpak Bhattacharyya

    This module continues the exploration of NLP stages, focusing on advanced techniques and their applications. It covers:

    • Advanced tokenization methods.
    • Challenges in parsing complex sentences.
    • Contextual analysis in NLP.
    • Integration of machine learning techniques in NLP.

    Students will learn about the evolution of NLP methodologies and their practical implications in real-world applications.

  • Mod-01 Lec-04 Two approaches to NLP
    Prof. Pushpak Bhattacharyya

    This module introduces two primary approaches to NLP: rule-based and statistical methods. Key areas of focus include:

    • Differences and similarities between rule-based and statistical approaches.
    • Advantages and limitations of each method.
    • Use cases for applying both approaches in practical scenarios.
    • Hybrid models that combine both methodologies.

    Students will understand the foundations of these approaches and how they shape modern NLP systems.

  • This module focuses on sequence labeling and the Noisy Channel model, essential concepts in NLP. Topics covered include:

    • Introduction to sequence labeling tasks.
    • Application of the Noisy Channel model in NLP.
    • Understanding the mathematical foundations behind these concepts.
    • Real-world applications and examples.

    Students will learn how these methods help in improving the accuracy and efficiency of NLP tasks.

  • This module examines the Argmax based computation method and its relevance to NLP. Key topics include:

    • The principles of Argmax in decision-making processes.
    • Applications in various NLP tasks.
    • Challenges and limitations of Argmax based computations.
    • Comparative analysis with other computational methods.

    Students will gain a deeper understanding of how Argmax contributes to effective NLP solutions.

  • Mod-01 Lec-07 Argmax Based Computation
    Prof. Pushpak Bhattacharyya

    This module applies the Noisy Channel model to various NLP tasks, demonstrating its practical utility. Topics include:

    • Real-world examples of Noisy Channel applications.
    • How it improves text processing accuracy.
    • Challenges in implementing this model.
    • Future trends in Noisy Channel applications.

    Students will learn how to leverage this model to enhance NLP systems effectively.

  • This module provides a brief overview of probabilistic parsing and introduces the concept of Part of Speech (PoS) tagging. It includes:

    • Fundamentals of probabilistic parsing techniques.
    • The role of PoS tagging in NLP.
    • Methods for determining word categories.
    • Evaluation metrics for PoS tagging accuracy.

    Students will gain insights into the importance of accurate parsing and tagging in understanding language structure.

  • This module dives deeper into Part of Speech tagging, focusing on advanced techniques and their applications. Key topics include:

    • Statistical methods for PoS tagging.
    • Challenges in tagging complex language structures.
    • Evaluation of tagging systems and accuracy measures.
    • Applications of PoS tagging in various NLP tasks.

    Students will explore the intricacies of PoS tagging and its critical role in language processing tasks.

  • Mod-01 Lec-10 Part of Speech Tagging
    Prof. Pushpak Bhattacharyya

    This module covers the counting methods used in Part of Speech tagging, with a focus on Indian languages. Topics include:

    • Counting techniques for PoS tagging.
    • Challenges faced in tagging Indian languages.
    • Evaluation of accuracy in different language contexts.
    • Importance of morphology in language processing.

    Students will understand how counting methods enhance tagging accuracy and their significance in multilingual NLP applications.

  • This module emphasizes the importance of accurate PoS tagging in NLP, discussing various measuring techniques. Key areas of focus include:

    • Measuring accuracy in PoS tagging systems.
    • Word categories and their significance.
    • Challenges in evaluating PoS tagging accuracy.
    • Best practices for improving tagging systems.

    Students will learn effective methods for assessing and enhancing tagging accuracy, essential for NLP applications.

  • This module explores the intersection of artificial intelligence and probability in NLP, particularly through Hidden Markov Models (HMMs). Key topics include:

    • Introduction to HMM and its principles.
    • Applications of HMM in NLP tasks.
    • Challenges and limitations of HMMs.
    • Comparative analysis with other modeling techniques.

    Students will gain insights into the role of HMMs in probabilistic modeling and their impact on NLP solutions.

  • This module provides a detailed examination of Hidden Markov Models (HMMs) and their application in NLP. Topics include:

    • Mathematical foundations of HMMs.
    • Training methods for HMMs.
    • Applications in speech recognition and tagging.
    • Evaluation techniques for HMM performance.

    Students will learn how HMMs operate and their crucial role in various NLP functions.

  • This module highlights the evaluation metrics used in NLP, focusing on precision, recall, F-score, and Mean Average Precision (MAP). Key points include:

    • Definitions and significance of each metric.
    • How to calculate and interpret these metrics.
    • Real-world applications of evaluation metrics in NLP tasks.
    • Challenges in measuring NLP performance accurately.

    Students will learn how to effectively assess NLP models and the importance of metrics in evaluating their performance.

  • This module introduces semantic relations and discusses the Universal Networking Language (UNL) framework. Topics include:

    • Understanding semantic roles and their importance.
    • Overview of UNL and its applications in NLP.
    • Challenges in semantic relation extraction.
    • Future trends in semantic analysis.

    Students will grasp the significance of semantic relations in understanding language and their applications in NLP systems.

  • Mod-01 Lec-16 AI and Probability; HMM
    Prof. Pushpak Bhattacharyya

    This module focuses on semantic role extraction and its relevance in NLP. Key areas covered include:

    • Techniques for semantic role labeling.
    • Applications in various NLP tasks.
    • Challenges faced in accurate role extraction.
    • Comparative analysis with other extraction methods.

    Students will learn how semantic role extraction enhances the understanding of language context and meaning in NLP.

  • Mod-01 Lec-17 HMM
    Prof. Pushpak Bhattacharyya

    This module provides a comprehensive overview of the Baum-Welch algorithm and its application in training Hidden Markov Models (HMM). Key focus areas include:

    • Understanding the Baum-Welch algorithm's principles.
    • Applications of the algorithm in NLP.
    • Challenges in implementing the algorithm.
    • Future directions in HMM training methodologies.

    Students will learn how the Baum-Welch algorithm is essential for optimizing HMM performance in various NLP applications.

  • This module delves into the Hidden Markov Model (HMM) and its applications in the field of natural language processing. Learners will explore the concept of the Viterbi algorithm, which is pivotal for decoding HMM. The module also covers the Forward-Backward algorithm, providing a comprehensive understanding of how probabilities are computed in sequence models. These algorithms are essential for tasks like speech recognition and part-of-speech tagging.

    By the end of the module, students will have a solid grasp of the mathematical foundation behind these algorithms and how they are implemented in practical NLP applications.

  • This continuation module further examines the intricacies of Hidden Markov Models (HMM) and the Viterbi algorithm. It extends the discussion on the Forward-Backward algorithm, emphasizing its role in improving the accuracy of sequence predictions. Additionally, the module provides insights into optimizing HMM for diverse linguistic tasks, ensuring students gain a deep understanding of these critical computational methods.

    The module aims to equip learners with advanced skills for implementing and fine-tuning HMMs in various natural language processing scenarios.

  • This module introduces the Baum-Welch algorithm, a cornerstone technique for training Hidden Markov Models (HMM). Students will learn how to use this algorithm for optimizing model parameters through unsupervised learning. The module also revisits the Forward-Backward algorithm, demonstrating its application in calculating likelihoods during the training phase.

    By understanding these algorithms, students will be able to enhance the performance of HMMs in natural language processing tasks, making them more effective in real-world applications.

  • This module continues to explore the Baum-Welch algorithm, offering an in-depth analysis of its functional mechanisms. Students will gain a hands-on understanding of how to iteratively refine model parameters for optimal performance. The module emphasizes the significance of convergence and stability in the training process, ensuring that learners can apply these principles effectively in their NLP projects.

    Through practical examples, students will become proficient in utilizing the Baum-Welch algorithm for enhancing the accuracy of HMM-based systems.

  • This module discusses the intersection of Natural Language Processing (NLP) and Information Retrieval (IR). Students will explore how NLP techniques enhance information retrieval systems, enabling more accurate and context-aware search results. The module covers the foundational principles of IR and illustrates how linguistic analysis contributes to the development of sophisticated search algorithms.

    By the end of the module, learners will understand the symbiotic relationship between NLP and IR, preparing them to innovate in fields such as search engines and data analysis.

  • Mod-01 Lec-23 CLIA; IR Basics
    Prof. Pushpak Bhattacharyya

    This module introduces Cross-Lingual Information Access (CLIA) and the basic principles of Information Retrieval (IR). Students will learn about the challenges and solutions in accessing information across different languages. The module covers the essential components of IR systems and how they are adapted for multilingual contexts, enhancing the accessibility and effectiveness of global information systems.

    Through real-world examples, students will gain insights into the complexities of cross-lingual data retrieval and the technologies driving these advancements.

  • Mod-01 Lec-24 IR Models: Boolean Vector
    Prof. Pushpak Bhattacharyya

    This module delves into the Boolean and Vector Space Models of Information Retrieval (IR). Students will explore the theoretical underpinnings and practical applications of these models in information retrieval systems. The module highlights the strengths and limitations of each approach, providing insights into their use cases in modern search engines and data analysis tools.

    By understanding these models, learners will be equipped to design and implement more efficient IR systems tailored to specific information retrieval needs.

  • This module explores the intricate relationship between Natural Language Processing (NLP) and Information Retrieval (IR). Students will learn how NLP techniques are leveraged to enhance IR systems, leading to more sophisticated and accurate search results. The module discusses the challenges and opportunities in integrating NLP and IR, focusing on the benefits of combining linguistic and statistical approaches.

    By the end of the module, learners will gain an in-depth understanding of how NLP can be used to improve the effectiveness of IR systems across various applications.

  • This module discusses how Natural Language Processing (NLP) has utilized Information Retrieval (IR) techniques to advance its methodologies. Students will explore how IR contributes to NLP tasks such as document classification and clustering. The module introduces the concept of Latent Semantic Analysis, highlighting its impact on improving the performance of NLP systems.

    Through practical examples, learners will gain insights into the synergy between NLP and IR, equipping them with the skills to innovate in both fields.

  • This module introduces the Least Squares Method and Principal Component Analysis (PCA) as foundational techniques for data dimensionality reduction. Students will learn how these methods are applied in the context of Latent Semantic Indexing (LSI) to enhance the efficiency and accuracy of information retrieval systems. The module illustrates the process of transforming high-dimensional data into lower-dimensional spaces, a crucial step in improving computational efficiency.

    By mastering these techniques, learners will be able to apply them to various NLP and IR tasks, optimizing data processing and analysis.

  • This module continues to explore Principal Component Analysis (PCA) and introduces Singular Value Decomposition (SVD) as advanced techniques for Latent Semantic Indexing (LSI). Students will understand how SVD enhances the dimensionality reduction process, leading to more efficient data representation and retrieval. The module provides a detailed analysis of the mathematical principles underlying these techniques and their practical applications in NLP and IR.

    Through hands-on exercises, learners will develop the skills to implement PCA and SVD in real-world scenarios, optimizing data-driven applications.

  • This module covers the concept of WordNet and its application in Word Sense Disambiguation (WSD). Students will explore how WordNet, a lexical database, is used to determine the meanings of words in context. The module discusses the importance of semantic networks in enhancing the accuracy of natural language understanding systems, providing insights into their integration with WSD algorithms.

    By the end of the module, learners will understand how to leverage WordNet for improving the precision of language interpretation tasks.

  • This module continues the exploration of WordNet and Word Sense Disambiguation (WSD). Students will delve deeper into the techniques for leveraging WordNet to resolve ambiguities in natural language. The module emphasizes the practical applications of WSD in various linguistic tasks, highlighting the significance of accurate word sense identification for improving language processing systems.

    Through case studies and examples, learners will gain a comprehensive understanding of the challenges and solutions in implementing WSD using WordNet.

  • This module introduces the concept of metonymy and its impact on Word Sense Disambiguation (WSD) using WordNet. Students will explore how metonymic expressions pose challenges to traditional WSD techniques and the strategies employed to address these challenges. The module highlights the role of semantic networks in understanding and interpreting metonymic language, providing insights into the nuances of natural language processing.

    By understanding metonymy, learners will be better equipped to handle complex language phenomena in NLP tasks.

  • Mod-01 Lec-32 Word Sense Disambiguation
    Prof. Pushpak Bhattacharyya

    This module provides a comprehensive overview of Word Sense Disambiguation (WSD) techniques. Students will explore various methods for determining word meanings in context, emphasizing the importance of semantic analysis. The module covers both supervised and unsupervised approaches to WSD, highlighting their strengths and limitations.

    Through practical exercises, learners will gain the skills to implement WSD algorithms in real-world applications, enhancing the accuracy and effectiveness of language processing systems.

  • This module explores overlap-based and supervised methods for Word Sense Disambiguation (WSD). Students will learn how semantic overlap between textual contexts is used to resolve word ambiguities. The module provides insights into the development and implementation of supervised WSD models, illustrating their application in enhancing natural language understanding systems.

    By mastering these methods, learners will be able to design robust WSD systems that improve the precision of language interpretation tasks.

  • This module provides an in-depth analysis of supervised and unsupervised methods for Word Sense Disambiguation (WSD). Students will explore the advantages and limitations of each approach, learning how to select the appropriate method for specific linguistic tasks. The module emphasizes the role of annotated corpora in supervised learning and the use of clustering algorithms in unsupervised techniques.

    By the end of the module, learners will be equipped with the knowledge to implement effective WSD strategies in various natural language processing applications.

  • This module focuses on Word Sense Disambiguation (WSD), covering both semi-supervised and unsupervised methods. Students will explore various algorithms and techniques to determine the correct meaning of words based on context. Key topics include:

    • Understanding the challenges of WSD.
    • Comparative analysis of semi-supervised vs. unsupervised methods.
    • Implementation of algorithms for practical applications.
    • Evaluation metrics for assessing WSD effectiveness.

    By the end of this module, students will be equipped with the necessary skills to apply WSD techniques in natural language processing tasks.

  • This module dives into resource-constrained Word Sense Disambiguation and its relationship with parsing. Students will learn how limited resources can affect disambiguation tasks and parsing strategies. Topics covered include:

    • Analysis of resource constraints in NLP.
    • Techniques for effective WSD under resource limitations.
    • Integration of parsing approaches with WSD.
    • Case studies showcasing practical applications.

    Students will gain insights into optimizing NLP processes in environments with limited resources, enhancing their problem-solving skills.

  • Mod-01 Lec-37 Parsing
    Prof. Pushpak Bhattacharyya

    This module provides an in-depth look at parsing, focusing on various parsing techniques and their applications. Students will investigate both syntactic and semantic parsing strategies, including:

    • Understanding parsing fundamentals and terminologies.
    • Exploring different parsing techniques: top-down, bottom-up, etc.
    • Implementing parsing algorithms for real-world applications.
    • Analyzing parsing challenges in natural language processing.

    By the end of this module, students will have a solid grasp of parsing methodologies and their significance in NLP.

  • Mod-01 Lec-38 Parsing Algorithm
    Prof. Pushpak Bhattacharyya

    This module covers advanced parsing algorithms, providing insights into their design and implementation. Students will explore various algorithmic approaches to parsing, including:

    • Top-down and bottom-up parsing methods.
    • Probabilistic parsing techniques and their applications.
    • Challenges and solutions in implementing algorithms.
    • Real-world examples of parsing algorithms in action.

    Students will develop a deep understanding of how parsing algorithms function and their critical role in NLP tasks.

  • This module examines the complexities of parsing ambiguous sentences and introduces probabilistic parsing. Key topics include:

    • Identifying and resolving ambiguities in sentences.
    • Implementing probabilistic parsing methods.
    • Evaluating parsing techniques for ambiguous inputs.
    • Practical applications of probabilistic parsing in NLP.

    Students will learn how to analyze and parse sentences with inherent ambiguities effectively, enhancing their NLP toolkit.

  • This module focuses on various probabilistic parsing algorithms, emphasizing their theoretical foundations and practical applications. Topics covered include:

    • Understanding probabilistic models in parsing.
    • Exploring various probabilistic parsing algorithms.
    • Analyzing performance metrics for parsing.
    • Case studies highlighting successful implementations.

    Students will enhance their understanding of probabilistic parsing and its importance in developing robust NLP systems.