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

The simple linear regression model


In Example 4.6.1. Resistant line for the IO-CPU time of Chapter 4, Exploratory Analysis, we built a resistant line for CPU_Time as a function of the No_of_IO processes. The results were satisfactory in the sense that the fitted line was very close to covering all the data points (refer to the Resistant line for CPU_Time figure of Chapter 4, Exploratory Analysis). However, we need more statistical validation of the estimated values of the slope and intercept terms. Here, we take a different approach and state the linear regression model in more technical details.

The simple linear regression model is given by , where X is the covariate/independent variable, Y is the regressand/dependent variable, and ε is the unobservable error term. The parameters of the linear model are specified by and . Here, is the intercept term and corresponds to the value of Y when x = 0. The slope term, , reflects the change in the Y value for a unit change in X. It is also common...