## Welcome to class!

1. Introductions
2. Class overview
3. Getting R up and running

John Muschelli

Assistant Scientist, Department of Biostatistics

PhD in Biostatistics, ScM in Biostatistics

Email: [email protected]

Andrew Jaffe

Lead Investigator, Lieber Institute for Brain Development

Associate Professor, Department of Mental Health, JHSPH

PhD in Epidemiology, MHS in Bioinformatics

Email: [email protected]

## What is R?

• R is a language and environment for statistical computing and graphics

• R is the open source implementation of the S language, which was developed by Bell laboratories

• R is both open source and open development

(source: http://www.r-project.org/)

## Why R?

• Powerful and flexible

• Free (open source)

• Designed for statistical computing

• High level language

## Why not R?

• Fairly steep learning curve

• “Programming” oriented

• Minimal interface

• Little centralized support, relies on online community and package developers

• Annoying to update

• Slower, and more memory intensive, than the more traditional programming languages (C, Java, Perl, Python)

## Introductions

What do you hope to get out of the class?

Why else to use R?

## Learning Objectives

• Recoding and manipulating data
• Writing R functions and using add-on packages
• Making exploratory plots
• Understanding basic programming syntax
• Performing basic statistical tests

## Collection of R packages

We have an R package called jhur that will make sure all the packages are installed.

You can just copy and paste the below code into your console - we’ll explain what it all means in the next day or two

install.packages("remotes")
remotes::install_github("muschellij2/jhur")

Note it may take ~5-10 minutes to run.