Nonparametric Statistical Methods Using R

John Kloke, Joseph W. McKean

• Publisher: Chapman and Hall/CRC
• Year: 2014
• ISBN:
  9781498787277
• Edition: 1
• Topic: Mathematics
• Subtopic: Probability & Statistics
• Index: Mathematics

A Practical Guide to Implementing Nonparametric and Rank-Based ProceduresNonparametric Statistical Methods Using R covers traditional nonparametric methods and rank-based analyses, including estimation and inference for models ranging from simple location models to general linear and nonlinear models for uncorrelated and correlated responses. The a

Chapter 1

Getting Started with R

This chapter serves as a primer for R. We invite the reader to start his or her R session and follow along with our discussion. We assume the reader is familiar with basic summary statistics and graphics taught in standard introductory statistics courses. We present a short tour of the langage; those interested in a more thorough introduction are referred to a monograph on R (e.g., Chambers 2008). Also, there are a number of manuals available at the Comprehensive R Archive Network (CRAN) (http://cran.r-project.org/). An excellent overview, written by developers of R, is Venables and Ripley (2002).

R provides a built-in documentation system. Using the help function i.e. help(command) or ?command in your R session to bring up the help page (similar to a man page in traditional Unix) for the command. For example try: help(help) or help(median) or help(rfit). Of course, Google is another excellent resource.

1.1 R Basics

Without going into a lot of detail, R has the capability of handling character (strings), logical (TRUE or FALSE), and of course numeric data types. To illustrate the use of R we multiply the system defined constant pi by 2.

> 2*pi

[1] 6.283185

We usually want to save the result for later calculation, so assignment is important. Assignment in R is usually carried out using either the <- operator or the = operator. As an example, the following code computes the area of a circle with radius 4/3 and assigns it to the variable A:

> r<-4/3

> A<-pi*r^2

> A

[1] ...