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)

Data-Level Deep Learning Methods

You learned about various sampling methods in the previous chapters. Collectively, we call these methods data-level methods in this book. These methods include random undersampling, random oversampling, NearMiss, and SMOTE. We also explored how these methods work with classical machine learning algorithms.

In this chapter, we’ll explore how to apply familiar sampling methods to deep learning models. Deep learning offers unique opportunities to enhance these methods further. We’ll delve into elegant techniques to combine deep learning with oversampling and undersampling. Additionally, we’ll learn how to implement various sampling methods with a basic neural network. We’ll also cover dynamic sampling, which involves adjusting the data sample across multiple training iterations, using varying balancing ratios for each iteration. Then, we will learn to use some data augmentation techniques for both images and text. We’...