Python Machine Learning

CHAPTER 5Getting Started with Scikit‐learn for Machine Learning

Introduction to Scikit‐learn

In Chapters 2–4, you learned how to use Python together with libraries such as NumPy and Pandas to perform number crunching, data visualization, and analysis. For machine learning, you can also use these libraries to build your own learning models. However, doing so would require you to have a strong appreciation of the mathematical foundation for the various machine learning algorithms—not a trivial matter.

Instead of implementing the various machine learning algorithms manually by hand, fortunately, someone else has already done the hard work for you. Introducing Scikit‐learn, a Python library that implements the various types of machine learning algorithms, such as classification, regression, clustering, decision tree, and more. Using Scikit‐learn, implementing machine learning is now simply a matter of calling a function with the appropriate data so that you can fit and train the model.

In this chapter, first you will learn the various venues where you can get the sample datasets to learn how to perform machine learning. You will then learn how to use Scikit‐learn to perform simple linear regression on a simple dataset. Finally, you will learn how to perform data cleansing.

Getting Datasets

Often, one of the challenges in machine learning is obtaining sample datasets for experimentation. In machine learning, when you are just getting started with an algorithm, it is often useful ...