Book Image

Machine Learning for Imbalanced Data

By : Kumar Abhishek, Dr. Mounir Abdelaziz
Book Image

Machine Learning for Imbalanced Data

By: Kumar Abhishek, Dr. Mounir Abdelaziz

Overview of this book

As machine learning practitioners, we often encounter imbalanced datasets in which one class has considerably fewer instances than the other. Many machine learning algorithms assume an equilibrium between majority and minority classes, leading to suboptimal performance on imbalanced data. This comprehensive guide helps you address this class imbalance to significantly improve model performance. Machine Learning for Imbalanced Data begins by introducing you to the challenges posed by imbalanced datasets and the importance of addressing these issues. It then guides you through techniques that enhance the performance of classical machine learning models when using imbalanced data, including various sampling and cost-sensitive learning methods. As you progress, you’ll delve into similar and more advanced techniques for deep learning models, employing PyTorch as the primary framework. Throughout the book, hands-on examples will provide working and reproducible code that’ll demonstrate the practical implementation of each technique. By the end of this book, you’ll be adept at identifying and addressing class imbalances and confidently applying various techniques, including sampling, cost-sensitive techniques, and threshold adjustment, while using traditional machine learning or deep learning models.
Table of Contents (15 chapters)

Ensemble Methods

Think of a top executive at a major company. They don’t make decisions on their own. Throughout the day, they need to make numerous critical decisions. How do they make those choices? Not alone, but by consulting their advisors.

Let’s say that an executive consults five different advisors from different departments, each proposing a slightly different solution based on their expertise, skills, and domain knowledge. To make the most effective decision, the executive combines the insights and opinions of all five advisors to create a hybrid solution that incorporates the best parts of each proposal. This scenario illustrates the concept of ensemble methods, where multiple weak classifiers are combined to create a stronger and more accurate classifier. By combining different approaches, ensemble methods can often achieve better performance than relying on a single classifier.

We can create a strong model through ensemble methods by combining the results...