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Probabilistic Graphical Models

Master graph-based probability models that simplify complex probabilistic computations. Learn how nodes and edges represent random variables and their dependencies for inference in speech recognition, image processing, and text analysis.

Fundamentals
Module 1
Understand the foundation of probabilistic graphical models. Learn graph structure definitions, directed vs undirected models, generative vs discriminative paradigms, and how graphs simplify probability computation through inference.

Topics Covered:

Graph Structure Definition
Directed vs Undirected Models
Generative vs Discriminative
Core Inference Goals
Medical Diagnosis Networks
Hidden Markov Models (HMM)
Module 2
Master sequential directed graph models with hidden states. Learn state and observation variables, three parameters (A, B, π), joint probability formulas, and three fundamental problems: evaluation, decoding (Viterbi), and learning (Baum-Welch).

Topics Covered:

State & Observation Variables
Transition & Emission Matrices
Forward/Backward Algorithms
Viterbi Algorithm
Baum-Welch Learning
Speech Recognition Examples
Markov Random Fields (MRF)
Module 3
Explore undirected graph probability models. Learn cliques and maximal cliques, potential functions (energy functions), joint distribution based on clique decomposition, and three Markov properties: global, local, and pairwise.

Topics Covered:

Cliques & Maximal Cliques
Potential Functions
Energy Functions
Three Markov Properties
Conditional Independence
Image Denoising Examples
Conditional Random Fields (CRF)
Module 4
Master discriminative undirected graph models for sequence labeling. Learn linear-chain CRF structure, transition and state feature functions, conditional probability formulas, and applications to part-of-speech tagging and named entity recognition.

Topics Covered:

Linear-Chain CRF
Feature Functions
Transition & State Features
Sequence Labeling
POS Tagging
Named Entity Recognition
Exact Inference
Module 5
Learn precise probability computation methods without approximation. Master variable elimination algorithms, belief propagation (message passing), marginal and conditional probability calculation, and when to use exact methods for acyclic graphs.

Topics Covered:

Variable Elimination
Belief Propagation
Message Passing
Marginal Probability
Conditional Probability
Tree Structure Inference
Approximate Inference
Module 6
Handle complex graphs and high-dimensional variables with approximation methods. Learn MCMC sampling (Metropolis-Hastings, Gibbs sampling), variational inference (ELBO, KL divergence, mean-field), and when to use each approach.

Topics Covered:

MCMC Sampling
Metropolis-Hastings
Gibbs Sampling
Variational Inference
ELBO & KL Divergence
Mean-Field Approximation
Topic Models (LDA)
Module 7
Master generative directed graph models for text analysis. Learn Latent Dirichlet Allocation (LDA), bag-of-words representation, Dirichlet distributions, document-topic and topic-word distributions, parameter estimation, and topic inference for document clustering.

Topics Covered:

LDA Model Structure
Bag-of-Words
Dirichlet Distribution
Document-Topic Distribution
Topic-Word Distribution
Text Topic Modeling

Suggested Learning Paths

Fundamentals Path

Start with core concepts

  • Fundamentals
  • Hidden Markov Models
  • Markov Random Fields

Inference Path

Master inference methods

  • Exact Inference
  • Approximate Inference

Applications Path

Focus on practical applications

  • Conditional Random Fields
  • Topic Models

Why Learn Probabilistic Graphical Models?

Simplify Complex Probability

Graph structures provide intuitive visualizations of probabilistic relationships, making complex joint distributions manageable through factorization.

Real-World Applications

Essential for speech recognition (HMM), image processing (MRF), natural language processing (CRF, LDA), and many other domains requiring structured probabilistic reasoning.

Foundation for Advanced ML

Understanding graphical models provides the foundation for deep learning, variational autoencoders, and other modern probabilistic machine learning techniques.

Industry Standard

Widely used in industry for natural language processing, computer vision, bioinformatics, and recommendation systems where structured probabilistic reasoning is crucial.