Book Image

Designing Machine Learning Systems with Python

By : David Julian
Book Image

Designing Machine Learning Systems with Python

By: David Julian

Overview of this book

Machine learning is one of the fastest growing trends in modern computing. It has applications in a wide range of fields, including economics, the natural sciences, web development, and business modeling. In order to harness the power of these systems, it is essential that the practitioner develops a solid understanding of the underlying design principles. There are many reasons why machine learning models may not give accurate results. By looking at these systems from a design perspective, we gain a deeper understanding of the underlying algorithms and the optimisational methods that are available. This book will give you a solid foundation in the machine learning design process, and enable you to build customised machine learning models to solve unique problems. You may already know about, or have worked with, some of the off-the-shelf machine learning models for solving common problems such as spam detection or movie classification, but to begin solving more complex problems, it is important to adapt these models to your own specific needs. This book will give you this understanding and more.
Table of Contents (16 chapters)
Designing Machine Learning Systems with Python
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Free Chapter
1
Thinking in Machine Learning
Index

Transforming features


When we transform features, our aim, obviously, is to make them more useful to our models. This can be done by adding, removing, or changing information represented by the feature. A common feature transformation is that of changing the feature type. A typical example is binarization, that is, transforming a categorical feature into a set of binary ones. Another example is changing an ordinal feature into a categorical feature. In both these cases, we lose information. In the first instance, the value of a single categorical feature is mutually exclusive, and this is not conveyed by the binary representation. In the second instance, we lose the ordering information. These types of transformations can be considered inductive because they consist of a well-defined logical procedure that does not involve an objective choice apart from the decision to carry out these transformations in the first place.

Binarization can be easily carried out using the sklearn.preprocessing...