Book Image

Principles of Data Science - Third Edition

By : Sinan Ozdemir
Book Image

Principles of Data Science - Third Edition

By: Sinan Ozdemir

Overview of this book

Principles of Data Science bridges mathematics, programming, and business analysis, empowering you to confidently pose and address complex data questions and construct effective machine learning pipelines. This book will equip you with the tools to transform abstract concepts and raw statistics into actionable insights. Starting with cleaning and preparation, you’ll explore effective data mining strategies and techniques before moving on to building a holistic picture of how every piece of the data science puzzle fits together. Throughout the book, you’ll discover statistical models with which you can control and navigate even the densest or the sparsest of datasets and learn how to create powerful visualizations that communicate the stories hidden in your data. With a focus on application, this edition covers advanced transfer learning and pre-trained models for NLP and vision tasks. You’ll get to grips with advanced techniques for mitigating algorithmic bias in data as well as models and addressing model and data drift. Finally, you’ll explore medium-level data governance, including data provenance, privacy, and deletion request handling. By the end of this data science book, you'll have learned the fundamentals of computational mathematics and statistics, all while navigating the intricacies of modern ML and large pre-trained models like GPT and BERT.
Table of Contents (18 chapters)

Bayesian ideas revisited

In the last chapter, we talked very briefly about Bayesian ways of thinking. Recall that the Bayesian way of thinking is to let our data shape and update our beliefs. We start with a prior probability, or what we naïvely think about a hypothesis, and then we have a posterior probability, which is what we think about a hypothesis, given some data.

Bayes’ theorem

Bayes’ theorem is arguably the most well-known part of Bayesian inference. Recall that we previously defined the following:

  • P(A) = the probability that event A occurs
  • P(A|B) = the probability that A occurs, given that B occurred
  • P(A, B) = the probability that A and B occur
  • P(A, B) = P(A) * P(B|A)

That last bullet can be read as “the probability that both A and B occur is equal to the probability that A occurs x times the probability that B occurred, given that A has already occurred.”

Starting from the last bullet points, we know the...