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

3.4 ADDING AN INDEX FIELD

The data scientist may want to augment the data set with new variables that can enhance understanding. For example, not all data sets, including the bank_marketing data sets, come equipped with an ID field. Thus, we can add an index field to the data, which will serve two purposes: (i) it acts as an ID field for data sets without such a field and (ii) it tracks the sort order of the records in the database. In data science, we often repartition and re‐sort the data; it is therefore helpful to have an index field, in order to recover the original sort order when desired. How to add an index field using Python and R follows.

3.4.1 How to Add an Index Field Using Python

First, we need to open the required package, using the code discussed in the previous chapter.

import pandas as pd

Next, import the data set under the name bank_train by using the read_csv() command and specifying the file's location.

bank_train = pd.read_csv("C:/.../bank_marketing_training...