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

11.3 AN APPLICATION OF MULTIPLE REGRESSION MODELING

To illustrate multiple regression, we turn to the clothing_sales_training and clothing_sales_test data sets. The client has some data on customer spending and would like to estimate Sales_per_Visit, given three predictors:

  • Days between purchases (“Days,” Continuous: Average number of days between purchases.)
  • Credit Card (“CC,” Flag: Does the customer have a store credit card?)
  • Web Account (“Web,” Flag: Does the customer have a web account?)

So, our provisional regression equation will be:

equationSalesper^Visit=b0+b1(Daysbetweenpurchases)+b2(CreditCard)+b3(WebAccount)--

Because there is only one continuous predictor, it is not necessary to standardize the predictors. The results of the regression of Sales per Visit vs the three predictors for the training set are shown in Figure 11.1. We use the p‐values as a guide to tell us which variables belong in the model. Note that we are not...