Intro to R Crash Course, Part 1

Friday, September 25 — for anyone new to R

Friday, Sep 25, 12:10–1:00 PM, Asmundson 242. Basic R syntax, from scratch. Optional, but open to everyone — a good refresher even if you’ve used R before. Part 1 of 2 (continues Oct 2).


Quick self-check

Before we start, tell us where you’re at with R — this helps us pace the session. Tap the link below on your phone:

Submit your answer →

“How would you describe your R coding ability?” — Totally new to R · I’ve run others’ code · I’ve written my own code · I routinely use R to code and do analyses · I develop new tools in R

Before you arrive

If you haven’t already, install R and RStudio — see the Setup guide.

The script we’ll work through in class

This is the actual script — live, at the keyboard, not just slides. Follow along on your own laptop.

What’s in it (we’ll get as far as we get in 50 minutes — Part 2 on Oct 2 picks up where we leave off):

  • Objects and 1D types in R (numeric, character, logical)
  • Beyond numeric: factors, dates, and other types
  • Vectors: creating, indexing, and vectorized operations
  • Beyond 1D: lists and data frames
  • Files, directories, and reading in data (read.csv)
  • Basic plotting with ggplot2
  • The pipe operator |>
  • Beginner+ skills: writing your own functions, and for loops vs. apply-family functions (likely Oct 2 territory)

Data

The script reads in this dataset partway through — download it and keep it in your working directory:

Extra resources

Optional — if you’re new to R, or want more practice than we have time for in class.

Cheat sheets (quick reference, print or keep open in a tab):

  • Posit cheat sheets — RStudio IDE, data visualization (ggplot2), data transformation (dplyr/tidyr), and more, all one page each.

Guided tutorials / practice:

Free online book:

  • R for Data Science (2e) — the standard reference for the tidyverse approach to importing, wrangling, and visualizing data in R. More than you need for this course, but a good thing to have on hand.

Video:

  • StatQuest with Josh Starmer — short, clear explainer videos on R and statistics topics. A good channel to bookmark for later in the course too, once we get into the statistics fundamentals starting Mon 9/28.