Book Image

Data Cleaning and Exploration with Machine Learning

By : Michael Walker
Book Image

Data Cleaning and Exploration with Machine Learning

By: Michael Walker

Overview of this book

Many individuals who know how to run machine learning algorithms do not have a good sense of the statistical assumptions they make and how to match the properties of the data to the algorithm for the best results. As you start with this book, models are carefully chosen to help you grasp the underlying data, including in-feature importance and correlation, and the distribution of features and targets. The first two parts of the book introduce you to techniques for preparing data for ML algorithms, without being bashful about using some ML techniques for data cleaning, including anomaly detection and feature selection. The book then helps you apply that knowledge to a wide variety of ML tasks. You’ll gain an understanding of popular supervised and unsupervised algorithms, how to prepare data for them, and how to evaluate them. Next, you’ll build models and understand the relationships in your data, as well as perform cleaning and exploration tasks with that data. You’ll make quick progress in studying the distribution of variables, identifying anomalies, and examining bivariate relationships, as you focus more on the accuracy of predictions in this book. By the end of this book, you’ll be able to deal with complex data problems using unsupervised ML algorithms like principal component analysis and k-means clustering.
Table of Contents (23 chapters)
1
Section 1 – Data Cleaning and Machine Learning Algorithms
5
Section 2 – Preprocessing, Feature Selection, and Sampling
9
Section 3 – Modeling Continuous Targets with Supervised Learning
13
Section 4 – Modeling Dichotomous and Multiclass Targets with Supervised Learning
19
Section 5 – Clustering and Dimensionality Reduction with Unsupervised Learning

Chapter 14: Naïve Bayes Classification

In this chapter, we will examine situations where naïve Bayes might be a more efficient classifier than the ones we have examined so far. Naïve Bayes is a very intuitive and easy-to-implement classifier. Assuming our features are independent, we may even get improved performance over logistic regession, particularly if we are not using regularization with the latter.

In this chapter, we will discuss the fundamental assumptions of naïve Bayes and how the algorithm is used to tackle some of the modeling challenges we have already explored, as well as some new ones, such as text classification. We will consider when naïve Bayes is a good option and when it is not. We will also examine the interpretation of naïve Bayes models.

We will cover the following topics in this chapter:

  • Key concepts
  • Naïve Bayes classification models
  • Naïve Bayes for text classification