Book Image

Applied Supervised Learning with R

By : Karthik Ramasubramanian, Jojo Moolayil
Book Image

Applied Supervised Learning with R

By: Karthik Ramasubramanian, Jojo Moolayil

Overview of this book

R provides excellent visualization features that are essential for exploring data before using it in automated learning. Applied Supervised Learning with R helps you cover the complete process of employing R to develop applications using supervised machine learning algorithms for your business needs. The book starts by helping you develop your analytical thinking to create a problem statement using business inputs and domain research. You will then learn different evaluation metrics that compare various algorithms, and later progress to using these metrics to select the best algorithm for your problem. After finalizing the algorithm you want to use, you will study the hyperparameter optimization technique to fine-tune your set of optimal parameters. The book demonstrates how you can add different regularization terms to avoid overfitting your model. By the end of this book, you will have gained the advanced skills you need for modeling a supervised machine learning algorithm that precisely fulfills your business needs.
Table of Contents (12 chapters)
Applied Supervised Learning with R
Preface

Hyperparameter Optimization


Hyperparameter optimization is the process of optimizing or finding the most optimal set of hyperparameters for a machine learning model. A hyperparameter is a parameter that defines the macro characteristics for a machine learning model. It is basically a metaparameter for the model. Hyperparameters are different from model parameters; model parameters are learned by the model during the learning process, however, hyperparameters are set by the data scientist designing the model and cannot be learned by the model.

To understand the concept more intuitively, let's explore the topic in layman terms. Consider the example of a decision tree model. The tree structure with the root node, decision nodes, and leaf nodes are (akin to the beta coefficients in logistic regression) are learned through training (fitting) of data. When the model finally converges (finds the optimal set of values for model parameters), we have the final tree structure that defines the traversal...