Book Image

Data Science Projects with Python

By : Stephen Klosterman
Book Image

Data Science Projects with Python

By: Stephen Klosterman

Overview of this book

Data Science Projects with Python is designed to give you practical guidance on industry-standard data analysis and machine learning tools, by applying them to realistic data problems. You will learn how to use pandas and Matplotlib to critically examine datasets with summary statistics and graphs, and extract the insights you seek to derive. You will build your knowledge as you prepare data using the scikit-learn package and feed it to machine learning algorithms such as regularized logistic regression and random forest. You’ll discover how to tune algorithms to provide the most accurate predictions on new and unseen data. As you progress, you’ll gain insights into the working and output of these algorithms, building your understanding of both the predictive capabilities of the models and why they make these predictions. By then end of this book, you will have the necessary skills to confidently use machine learning algorithms to perform detailed data analysis and extract meaningful insights from unstructured data.
Table of Contents (9 chapters)
Data Science Projects with Python
Preface

Introduction


In the last two chapters, we have gained a thorough understanding of the workings of logistic regression. We have also gotten a lot of experience with using the scikit-learn package in Python to create logistic regression models.

In this chapter, we will introduce a powerful type of predictive model that takes a completely different approach from the logistic regression model: decision trees. The concept of using a tree process to make decisions is simple, and therefore, decision tree models are easy to interpret. However, a common criticism of decision trees is that they overfit the training data. In order to remedy this issue, researchers have developed ensemble methods, such as random forests, that combine many decision trees to work together and make better predictions than any individual tree could.

We will see that decision trees and random forests can improve the quality of our predictive modeling of the case study data beyond what we achieved so far with logistic regression...