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)

Hybrid Deep Learning Methods

In this chapter, we will talk about some of the hybrid deep learning techniques that combine the data-level (Chapter 7, Data-Level Deep Learning Methods) and algorithm-level (Chapter 8, Algorithm-Level Deep Learning Techniques) methods in some ways. This chapter contains some recent and more advanced techniques that can be challenging to implement, so it is recommended to have a good understanding of the previous chapters.

We will begin with an introduction to graph machine learning, clarifying how graph models exploit relationships within data to boost performance, especially for minority classes. Through a side-by-side comparison of a Graph Convolutional Network (GCN), XGBoost, and MLP models, using an imbalanced social network dataset, we will highlight the superior performance of the GCN.

We will continue to explore strategies to tackle class imbalance in deep learning, examining techniques that manipulate data distribution and prioritize challenging...