Book Image

Statistical Application Development with R and Python - Second Edition

Book Image

Statistical Application Development with R and Python - Second Edition

Overview of this book

Statistical Analysis involves collecting and examining data to describe the nature of data that needs to be analyzed. It helps you explore the relation of data and build models to make better decisions. This book explores statistical concepts along with R and Python, which are well integrated from the word go. Almost every concept has an R code going with it which exemplifies the strength of R and applications. The R code and programs have been further strengthened with equivalent Python programs. Thus, you will first understand the data characteristics, descriptive statistics and the exploratory attitude, which will give you firm footing of data analysis. Statistical inference will complete the technical footing of statistical methods. Regression, linear, logistic modeling, and CART, builds the essential toolkit. This will help you complete complex problems in the real world. You will begin with a brief understanding of the nature of data and end with modern and advanced statistical models like CART. Every step is taken with DATA and R code, and further enhanced by Python. The data analysis journey begins with exploratory analysis, which is more than simple, descriptive, data summaries. You will then apply linear regression modeling, and end with logistic regression, CART, and spatial statistics. By the end of this book you will be able to apply your statistical learning in major domains at work or in your projects.
Table of Contents (19 chapters)
Statistical Application Development with R and Python - Second Edition
Credits
About the Author
Acknowledgment
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
Index

Chapter 7. Logistic Regression Model

In this chapter, we will consider regression models when the regressand is dichotomous or binary in nature. The data is of the form , where the dependent variable Yi, i = 1, …, n are the observed binary output assumed to be independent (in the statistical sense) of each other, and the vector Xi, i = 1,…, n, are the covariates (independent variables in the sense of a regression problem) associated with Yi.

In the previous chapter, we considered linear regression models where the regressand was assumed to be continuous along with the assumption of normality for the error distribution. Here, we will consider a Gaussian (normal) model for the binary regression model, which is more widely known as the probit model. A more generic model has emerged during the past four decades in the form of logistic regression model. We will consider the logistic regression model for the rest of the chapter. The approach in this chapter will be on the following topics:

  • The binary...