Book Image

Practical Data Science with Python

By : Nathan George
Book Image

Practical Data Science with Python

By: Nathan George

Overview of this book

Practical Data Science with Python teaches you core data science concepts, with real-world and realistic examples, and strengthens your grip on the basic as well as advanced principles of data preparation and storage, statistics, probability theory, machine learning, and Python programming, helping you build a solid foundation to gain proficiency in data science. The book starts with an overview of basic Python skills and then introduces foundational data science techniques, followed by a thorough explanation of the Python code needed to execute the techniques. You'll understand the code by working through the examples. The code has been broken down into small chunks (a few lines or a function at a time) to enable thorough discussion. As you progress, you will learn how to perform data analysis while exploring the functionalities of key data science Python packages, including pandas, SciPy, and scikit-learn. Finally, the book covers ethics and privacy concerns in data science and suggests resources for improving data science skills, as well as ways to stay up to date on new data science developments. By the end of the book, you should be able to comfortably use Python for basic data science projects and should have the skills to execute the data science process on any data source.
Table of Contents (30 chapters)
1
Part I - An Introduction and the Basics
4
Part II - Dealing with Data
10
Part III - Statistics for Data Science
13
Part IV - Machine Learning
21
Part V - Text Analysis and Reporting
24
Part VI - Wrapping Up
28
Other Books You May Enjoy
29
Index

Hyperparameter optimization with search methods

We've already seen some hyperparameters for the few ML models we've examined so far, for example, the regularization strength hyperparameters for linear and logistic regression, or the value of k (for the number of nearest neighbors) in KNN.

Remember that hyperparameters are settings for the models that we choose, while parameters are values the models learn (like the coefficients for linear or logistic regression). Arguments provided to functions in Python and programming are also called parameters as we've seen previously.

We've also seen how there are cross-validation (CV) classes for linear and logistic regression in sklearn that allow us to optimize the C or alpha hyperparameter for regularization strength. However, these built-in CV methods only search for one optimum hyperparameter and don't have to worry about multiple hyperparameters at once. When we introduce more than one hyperparameter...