Chapter 10: Expert Systems & Natural Language Processing

10.1 Expert Systems

Computer systems that emulate human expert decision-making:

Examples: Medical diagnosis, financial planning

10.2 Natural Language Processing (NLP)

Techniques for understanding and generating human language:

Task Description Example
Tokenization Splitting text into words/tokens "Hello world" → ["Hello", "world"]
POS Tagging Identifying parts of speech "run" → verb or noun?
NER Named Entity Recognition "Apple in Cupertino" → ORG, LOC
Sentiment Analysis Determining emotional tone "I love this!" → positive

10.3 NLP Pipeline

  1. Text Preprocessing (cleaning, normalization)
  2. Feature Extraction (TF-IDF, word embeddings)
  3. Model Training (classifiers, neural networks)
  4. Evaluation (accuracy, precision, recall)

10.4 Modern NLP Techniques

10.5 Frequently Asked Exam Questions

  1. Explain the architecture of an expert system.
  2. Compare rule-based vs machine learning approaches in NLP.
  3. What are word embeddings and why are they useful?
  4. Describe the transformer architecture.
  5. How does sentiment analysis work?