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

14.5 CONFIRMING OUR METRICS

We will call Rule ID [1] “Rule 1.” Next, let us confirm the following values for Rule 1, using what we have learned so far:

  1. Support,
  2. Confidence,
  3. Lift.
  1. Support.
    equations=support=P(CSC=5and Churn=True)=transactions with bothCSC=5and Churn=Truetotal number of transactions=363000=1.2%--
    How did we get the 36? Support requires the intersection of two events, which can be found by generating the contingency table of customer service calls vs churn, shown in Figure 14.5. Note that the cell for CSC = 5 and Churn = True contains Count = 36, represented 1.2% of the total number of records.
  2. Confidence. Use the contingency table to confirm that this equals the conditional probability P(B ∣ A).
    equationconfidence=P(Churn=True|CSC=5)=P(Churn=True andCSC=5)P(CSC=5)=number of transactions containing bothCSC=5and Churn=Truenumber of transactions containingCSC=5--

    Both...