Book Image

Data Science Projects with Python - Second Edition

By : Stephen Klosterman
Book Image

Data Science Projects with Python - Second Edition

By: Stephen Klosterman

Overview of this book

If data is the new oil, then machine learning is the drill. As companies gain access to ever-increasing quantities of raw data, the ability to deliver state-of-the-art predictive models that support business decision-making becomes more and more valuable. In this book, you’ll work on an end-to-end project based around a realistic data set and split up into bite-sized practical exercises. This creates a case-study approach that simulates the working conditions you’ll experience in real-world data science projects. You’ll learn how to use key Python packages, including pandas, Matplotlib, and scikit-learn, and master the process of data exploration and data processing, before moving on to fitting, evaluating, and tuning algorithms such as regularized logistic regression and random forest. Now in its second edition, this book will take you through the end-to-end process of exploring data and delivering machine learning models. Updated for 2021, this edition includes brand new content on XGBoost, SHAP values, algorithmic fairness, and the ethical concerns of deploying a model in the real world. By the end of this data science book, you’ll have the skills, understanding, and confidence to build your own machine learning models and gain insights from real data.
Table of Contents (9 chapters)
Preface

Decision Trees

Decision trees and the machine learning models that are based on them, in particular, random forests and gradient boosted trees, are fundamentally different types of models than Generalized Linear Models (GLMs), such as logistic regression. GLMs are rooted in the theories of classical statistics, which have a long history. The mathematics behind linear regression was originally developed at the beginning of the 19th century, by Legendre and Gauss. Because of this, the normal distribution is also known as the Gaussian distribution.

In contrast, while the idea of using a tree process to make decisions is relatively simple, the popularity of decision trees as mathematical models has come about more recently. The mathematical procedures that we currently use for formulating decision trees in the context of predictive modeling were published in the 1980s. The reason for this more recent development is that the methods used to grow decision trees rely on computational power...