Book Image

The Data Science Workshop - Second Edition

By : Anthony So, Thomas V. Joseph, Robert Thas John, Andrew Worsley, Dr. Samuel Asare
5 (1)
Book Image

The Data Science Workshop - Second Edition

5 (1)
By: Anthony So, Thomas V. Joseph, Robert Thas John, Andrew Worsley, Dr. Samuel Asare

Overview of this book

Where there’s data, there’s insight. With so much data being generated, there is immense scope to extract meaningful information that’ll boost business productivity and profitability. By learning to convert raw data into game-changing insights, you’ll open new career paths and opportunities. The Data Science Workshop begins by introducing different types of projects and showing you how to incorporate machine learning algorithms in them. You’ll learn to select a relevant metric and even assess the performance of your model. To tune the hyperparameters of an algorithm and improve its accuracy, you’ll get hands-on with approaches such as grid search and random search. Next, you’ll learn dimensionality reduction techniques to easily handle many variables at once, before exploring how to use model ensembling techniques and create new features to enhance model performance. In a bid to help you automatically create new features that improve your model, the book demonstrates how to use the automated feature engineering tool. You’ll also understand how to use the orchestration and scheduling workflow to deploy machine learning models in batch. By the end of this book, you’ll have the skills to start working on data science projects confidently. By the end of this book, you’ll have the skills to start working on data science projects confidently.
Table of Contents (16 chapters)
Preface
12
12. Feature Engineering

Finding the Best Hyperparameterization

The best hyperparameterization depends on your overall objective in building a machine learning model in the first place. In most cases, this is to find the model that has the highest predictive performance on unseen data, as measured by its ability to correctly label data points (classification) or predict a number (regression).

The prediction of unseen data can be simulated using hold-out test sets or cross-validation, the former being the method used in this chapter. Performance is evaluated differently in each case, for instance, Mean Squared Error (MSE) for regression and accuracy for classification. We seek to reduce the MSE or increase the accuracy of our predictions.

Let's implement manual hyperparameterization in the following exercise.

Exercise 8.01: Manual Hyperparameter Tuning for a k-NN Classifier

In this exercise, we will manually tune a k-NN classifier, which was covered in Chapter 7, The Generalization of Machine...