Book Image

Python Machine Learning By Example - Third Edition

By : Yuxi (Hayden) Liu
Book Image

Python Machine Learning By Example - Third Edition

By: Yuxi (Hayden) Liu

Overview of this book

Python Machine Learning By Example, Third Edition serves as a comprehensive gateway into the world of machine learning (ML). With six new chapters, on topics including movie recommendation engine development with Naïve Bayes, recognizing faces with support vector machine, predicting stock prices with artificial neural networks, categorizing images of clothing with convolutional neural networks, predicting with sequences using recurring neural networks, and leveraging reinforcement learning for making decisions, the book has been considerably updated for the latest enterprise requirements. At the same time, this book provides actionable insights on the key fundamentals of ML with Python programming. Hayden applies his expertise to demonstrate implementations of algorithms in Python, both from scratch and with libraries. Each chapter walks through an industry-adopted application. With the help of realistic examples, you will gain an understanding of the mechanics of ML techniques in areas such as exploratory data analysis, feature engineering, classification, regression, clustering, and NLP. By the end of this ML Python book, you will have gained a broad picture of the ML ecosystem and will be well-versed in the best practices of applying ML techniques to solve problems.
Table of Contents (17 chapters)
15
Other Books You May Enjoy
16
Index

Summary

In this chapter, we started with an introduction to a typical machine learning problem, online ad click-through prediction, and its inherent challenges, including categorical features. We then looked at tree-based algorithms that can take in both numerical and categorical features.

Next, we had an in-depth discussion about the decision tree algorithm: its mechanics, its different types, how to construct a tree, and two metrics (Gini Impurity and entropy) that measure the effectiveness of a split at a node. After constructing a tree by hand, we implemented the algorithm from scratch.

You also learned how to use the decision tree package from scikit-learn and applied it to predict the CTR. We continued to improve performance by adopting the feature-based random forest bagging algorithm. Finally, the chapter ended with several ways in which to tune a random forest model, along with a bonus section in which we implemented a GBT model with XGBoost. Bagging...