Book Image

Hyperparameter Tuning with Python

By : Louis Owen
Book Image

Hyperparameter Tuning with Python

By: Louis Owen

Overview of this book

Hyperparameters are an important element in building useful machine learning models. This book curates numerous hyperparameter tuning methods for Python, one of the most popular coding languages for machine learning. Alongside in-depth explanations of how each method works, you will use a decision map that can help you identify the best tuning method for your requirements. You’ll start with an introduction to hyperparameter tuning and understand why it's important. Next, you'll learn the best methods for hyperparameter tuning for a variety of use cases and specific algorithm types. This book will not only cover the usual grid or random search but also other powerful underdog methods. Individual chapters are also dedicated to the three main groups of hyperparameter tuning methods: exhaustive search, heuristic search, Bayesian optimization, and multi-fidelity optimization. Later, you will learn about top frameworks like Scikit, Hyperopt, Optuna, NNI, and DEAP to implement hyperparameter tuning. Finally, you will cover hyperparameters of popular algorithms and best practices that will help you efficiently tune your hyperparameter. By the end of this book, you will have the skills you need to take full control over your machine learning models and get the best models for the best results.
Table of Contents (19 chapters)
1
Section 1:The Methods
8
Section 2:The Implementation
13
Section 3:Putting Things into Practice

Exploring Optuna

Optuna is a hyperparameter tuning package in Python that provides several hyperparameter tuning methods. We discussed how to utilize Optuna to conduct a hyperparameter tuning experiment in Chapter 9, Hyperparameter Tuning via Optuna. Here, we will discuss how to utilize this package to track those experiments.

Similar to Scikit-Optimize, Optuna provides very nice visualization modules to help us track the hyperparameter tuning experiments and as a guide for us to decide which subspace to search in the next trial. Four visualization modules can be utilized, as shown here. All of them expect the study object (see Chapter 9, Hyperparameter Tuning via Optuna) as input. Please see the full code in this book’s GitHub repository:

  • plot_contour: This is used to visualize the relationship between hyperparameters (as well as the objective function scores) in the form of contour plots:

Figure 13.10 – Contour plot

  • plot_optimization_history...