Book Image

Data Science Using Python and R

By : Chantal D. Larose, Daniel T. Larose
Book Image

Data Science Using Python and R

By: Chantal D. Larose, Daniel T. Larose

Overview of this book

Data science is hot. Bloomberg named a data scientist as the ‘hottest job in America’. Python and R are the top two open-source data science tools using which you can produce hands-on solutions to real-world business problems, using state-of-the-art techniques. Each chapter in the book presents step-by-step instructions and walkthroughs for solving data science problems using Python and R. You’ll learn how to prepare data, perform exploratory data analysis, and prepare to model the data. As you progress, you’ll explore what are decision trees and how to use them. You’ll also learn about model evaluation, misclassification costs, naïve Bayes classification, and neural networks. The later chapters provide comprehensive information about clustering, regression modeling, dimension reduction, and association rules mining. The book also throws light on exciting new topics, such as random forests and general linear models. The book emphasizes data-driven error costs to enhance profitability, which avoids the common pitfalls that may cost a company millions of dollars. By the end of this book, you’ll have enough knowledge and confidence to start providing solutions to data science problems using R and Python.
Table of Contents (20 chapters)
Free Chapter
1
ABOUT THE AUTHORS
17
INDEX
18
END USER LICENSE AGREEMENT

4.1 EDA VERSUS HT

Clients or analysts often have a priori hypotheses that they would like the data to test. An example of such a hypothesis is: Do cellphone users have a higher rate of positive responses than landline users? The resulting hypothesis test (HT) could be carried out using either classical statistical methods or using the cross‐validation methods of data science (Chapter 5).

On the other hand, the client or the analyst may not have any salient a priori notions about what the data might uncover. In such cases, they would prefer to use exploratory data analysis (EDA) or graphical data analysis. EDA allows the user to:

  • Use graphics to explore the relationship between the predictor variables and the target variable.
  • Use graphics and tables to derive new variables that will increase predictive value.
  • Use binning productively, to increase predictive value.

In this chapter, we will continue to explore the bank_marketing_training data set from Chapter 3. We begin by using...