Bayesian inference is a statistical method that updates probabilities based on evidence. It's rooted in Bayes' Theorem, which provides a mathematical framework for calculating conditional probabilities. Here's a breakdown of its core concepts:

Key Principles

  • Prior Knowledge: Initial beliefs about parameters before observing data
    Prior Distribution
  • Likelihood: Probability of observing data given a hypothesis
    Likelihood Function
  • Posterior Distribution: Updated beliefs after incorporating evidence
    Posterior Distribution
  • Evidence (Marginal Likelihood): Normalizing factor for Bayesian updating

Applications

  • Machine Learning: Used in probabilistic models like Naive Bayes classifiers
  • Medical Diagnosis: Calculating disease probabilities based on symptoms
  • Finance: Risk assessment and predictive modeling
  • Natural Language Processing: Spam filtering and text classification

Comparison with Frequentist Approach

Feature Bayesian Inference Frequentist Statistics
Uncertainty Handling Probabilistic (Bayesian) Frequentist (confidence intervals)
Prior Knowledge Incorporates prior beliefs Does not use prior knowledge
Computation Often uses MCMC methods Relies on analytical solutions

For further reading, explore our guide on Bayesian Networks or Markov Chain Monte Carlo (MCMC) Methods. Dive deeper into probability theory with Probability Fundamentals.

Bayesian Network
Markov Chain Monte Carlo