Chapter 9: Inferring Probability Models from Data

Chapter 9: Inferring Probability Models from Data#

This chapter covers methods for estimating parameters of probability models from data. We explore both frequentist (Maximum Likelihood) and Bayesian approaches.

Learning Objectives#

After completing this chapter, you will be able to:

  • Understand the likelihood function

  • Compute maximum likelihood estimates (MLE)

  • Apply Bayesian inference with prior and posterior distributions

  • Use conjugate priors for analytical solutions

  • Compute maximum a posteriori (MAP) estimates

  • Compare frequentist and Bayesian approaches

  • Apply these methods to common distributions

Chapter Outline#

  1. Maximum Likelihood Estimation - The frequentist approach

  2. Bayesian Inference Basics - Prior, likelihood, and posterior

  3. Conjugate Priors - Analytical Bayesian inference

  4. Applications - Real-world examples

Why This Matters#

Parameter estimation is fundamental to:

  • Machine Learning: Training models on data

  • Statistics: Fitting distributions to observations

  • Science: Estimating physical constants from experiments

  • Engineering: System identification and calibration

  • Finance: Risk modeling and option pricing

Two Philosophies#

Frequentist (MLE)#

“Parameters are fixed but unknown. Data is random. Find the parameter value that makes the observed data most likely.”

Bayesian#

“Parameters are uncertain (random). Update beliefs about parameters using data via Bayes’ theorem.”

Let’s explore both!