Book Image

Bayesian Analysis with Python

Book Image

Bayesian Analysis with Python

Overview of this book

The purpose of this book is to teach the main concepts of Bayesian data analysis. We will learn how to effectively use PyMC3, a Python library for probabilistic programming, to perform Bayesian parameter estimation, to check models and validate them. This book begins presenting the key concepts of the Bayesian framework and the main advantages of this approach from a practical point of view. Moving on, we will explore the power and flexibility of generalized linear models and how to adapt them to a wide array of problems, including regression and classification. We will also look into mixture models and clustering data, and we will finish with advanced topics like non-parametrics models and Gaussian processes. With the help of Python and PyMC3 you will learn to implement, check and expand Bayesian models to solve data analysis problems.
Table of Contents (15 chapters)
Bayesian Analysis with Python
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Bayes factors


A common alternative to evaluate and compare models in the Bayesian world (at least in some of its countries) are the Bayes factors.

One problem with Bayes factors is that their computation can be highly sensitive to aspects of the priors that have no practical effect on the posterior distribution of individual models. You may have noticed in previous examples that, in general, having a normal prior with a standard deviation of 100 is the same as having one with a standard deviation of 1,000, Instead, Bayes factors will be generally affected by these kind of changes in the model. Another problem with Bayes factors is that their computations can be more difficult than inference. One final criticism is that Bayes factors can be used as a Bayesian way of doing hypothesis testing; there is nothing wrong in this per se, but many authors have pointed out that an inference or modeling approach, similar to the one used in this book, is better suited to most problems than the generally...