Book Image

Hands-On Exploratory Data Analysis with R

By : Radhika Datar, Harish Garg
Book Image

Hands-On Exploratory Data Analysis with R

By: Radhika Datar, Harish Garg

Overview of this book

Hands-On Exploratory Data Analysis with R will help you build a strong foundation in data analysis and get well-versed with elementary ways to analyze data. You will learn how to understand your data and summarize its characteristics. You'll also study the structure of your data, and you'll explore graphical and numerical techniques using the R language. This book covers the entire exploratory data analysis (EDA) process—data collection, generating statistics, distribution, and invalidating the hypothesis. As you progress through the book, you will set up a data analysis environment with tools such as ggplot2, knitr, and R Markdown, using DOE Scatter Plot and SML2010 for multifactor, optimization, and regression data problems. By the end of this book, you will be able to successfully carry out a preliminary investigation on any dataset, uncover hidden insights, and present your results in a business context.
Table of Contents (17 chapters)
Free Chapter
1
Section 1: Setting Up Data Analysis Environment
7
Section 2: Univariate, Time Series, and Multivariate Data
11
Section 3: Multifactor, Optimization, and Regression Data Problems
14
Section 4: Conclusions

Histogram plots

A histogram includes an accurate representation of the distribution of numerical data. It includes a rough estimation of the probability distribution with the continuous variable. It differs from a bar graph. A bar graph compares two variables, and a histogram just one. In this section, we will focus on the use of histogram plots and how to draw and customize them. The iris dataset includes fewer attributes, so we can customize them as and when required.

Before understanding the customization of histograms with ggplot2, we should understand the normal plotting of the iris dataset. The difference between normal plotting and the plots created with ggplot2 will be clearly visible from the output screenshots.

The following command is executed to create a normal histogram:

> hist(iris$Sepal.Width, freq=NULL, density=NULL, breaks=12,
+ xlab="Sepal Width"...