Book Image

Mastering Machine Learning Algorithms

Book Image

Mastering Machine Learning Algorithms

Overview of this book

Machine learning is a subset of AI that aims to make modern-day computer systems smarter and more intelligent. The real power of machine learning resides in its algorithms, which make even the most difficult things capable of being handled by machines. However, with the advancement in the technology and requirements of data, machines will have to be smarter than they are today to meet the overwhelming data needs; mastering these algorithms and using them optimally is the need of the hour. Mastering Machine Learning Algorithms is your complete guide to quickly getting to grips with popular machine learning algorithms. You will be introduced to the most widely used algorithms in supervised, unsupervised, and semi-supervised machine learning, and will learn how to use them in the best possible manner. Ranging from Bayesian models to the MCMC algorithm to Hidden Markov models, this book will teach you how to extract features from your dataset and perform dimensionality reduction by making use of Python-based libraries such as scikit-learn v0.19.1. You will also learn how to use Keras and TensorFlow 1.x to train effective neural networks. If you are looking for a single resource to study, implement, and solve end-to-end machine learning problems and use-cases, this is the book you need.
Table of Contents (22 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
13
Deep Belief Networks
Index

Ensemble learning as model selection


This is not a proper ensemble learning technique, but it is sometimes known as bucketing. In the previous section, we have discussed how a few strong learners with different peculiarities can be employed to make up a committee. However, in many cases, a single learner is enough to achieve a good bias-variance trade-off but it's not so easy to choose among the whole Machine Learning algorithm population. For this reason, when a family of similar problems must be solved (they can differ but it's better to consider scenarios that can be easily compared), it's possible to create an ensemble containing several models and use cross-validation to find the one whose performances are the best. At the end of the process, a single learner will be used, but its choice can be considered like a grid search with a voting system. Sometimes this technique can unveil important differences even using similar datasets. For example, during the development of a system, a first...