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layout: default
title: Welcome
output: bookdown::html_chapter
---
  
## Prerequsitives

You will need to have R installed on your computer to run the code in this chapter, as well as the RStudio IDE, a free program that makes it easier to use R. You can learn how to install both in *Appendix A: Getting Started*.

You will also need to install the `tidyr`, `dplyr`, `devtools`, and `DSR` packages. To install, `tidyr`, `dplyr`, and `devtools`, open RStudio and run the command

```{r eval = FALSE}
install.packages(c("tidyr", "dplyr", "devtools"))
```

`DSR` is a collection of data sets that I have assembled for this book and saved online as a github repository ([github.com/garrettgman/DSR](http://github.com/garrettgman/DSR)). To install `DSR`, run the command

```{r eval = FALSE}
devtools::install_github("garrettgman/DSR")
```

To use the packages, load them with `library()`, i.e.