Book Image

Ensemble Machine Learning Cookbook

By : Dipayan Sarkar, Vijayalakshmi Natarajan
Book Image

Ensemble Machine Learning Cookbook

By: Dipayan Sarkar, Vijayalakshmi Natarajan

Overview of this book

Ensemble modeling is an approach used to improve the performance of machine learning models. It combines two or more similar or dissimilar machine learning algorithms to deliver superior intellectual powers. This book will help you to implement popular machine learning algorithms to cover different paradigms of ensemble machine learning such as boosting, bagging, and stacking. The Ensemble Machine Learning Cookbook will start by getting you acquainted with the basics of ensemble techniques and exploratory data analysis. You'll then learn to implement tasks related to statistical and machine learning algorithms to understand the ensemble of multiple heterogeneous algorithms. It will also ensure that you don't miss out on key topics, such as like resampling methods. As you progress, you’ll get a better understanding of bagging, boosting, stacking, and working with the Random Forest algorithm using real-world examples. The book will highlight how these ensemble methods use multiple models to improve machine learning results, as compared to a single model. In the concluding chapters, you'll delve into advanced ensemble models using neural networks, natural language processing, and more. You’ll also be able to implement models such as fraud detection, text categorization, and sentiment analysis. By the end of this book, you'll be able to harness ensemble techniques and the working mechanisms of machine learning algorithms to build intelligent models using individual recipes.
Table of Contents (14 chapters)

Bootstrapping

Bootstrapping is based on the jackknife method, which was proposed by Quenouille in 1949, and then refined by Tukey in 1958. The jackknife method is used for testing hypotheses and estimating confidence intervals. It's obtained by calculating the estimate after leaving out each observation and then computing the average of these calculations. With a sample of size N, the jackknife estimate can be found by aggregating the estimates of every N-1 sized sub-sample. It's similar to bootstrap samples, but while the bootstrap method is sampling with replacement, the jackknife method samples the data without replacement.

Bootstrapping is a powerful, non-parametric resampling technique that's used to assess the uncertainty in the estimator. In bootstrapping, a large number of samples with the same size are drawn repeatedly from an original sample. This allows...