Quarto + R Intro

Lecture 2

Dr. Elijah Meyer

Duke University
STA 199 - Summer 2023

2023-08-31

Checklist

– Are you on Slack?

– Have you reserved a Duke 198/199 container?

– Have you accepted your GitHub organization invite?

– You can find ae-01 here! We will clone it together as a class

– Chat with TA before or after class / if you are not in Slack or the GitHub org

Announcements

– AE grading (Drop/Add ends - Sep-8th)

– If you are sick and need to request a recording, please do so after lecture is completed

– Lab-0

Warm Up 1: Types of Variables

– Height

– Weight

– Zip Code

– Coffee Drinker

Warm Up 1: Types of Variables

Warm Up 2: Variables

– Explanatory Variable

– Response Variable

Warm Up 2: Variables

From the text: When we suspect one variable might causally; predict; influence change in another we label the first variable the explanatory variable and the second the response variable

Warm Up 3: Types of Studies

– Observational Study

– Experiment

Warm Up 3: Types of Studies

Researchers perform an observational study when they collect data in a way that does not directly interfere with how the data arise.

In an experiment, we often manipulate; control; fix; administer the explanatory variable.

Clone ae-01

– This is a similar process to how you will start off each class period

– Next Tuesday, AEs will be in the STA199-f23-1 GitHub organization

Demo: clone ae-01

Goals for today

Basics we will use throughout the semester

R and RStudio
Quarto Documents
Practice

What is R and RStudio?

– R is a statistical programming language

– RStudio is a convenient interface for R

For Today

– R essentials

– R-layout tour

Some R essentials

– Functions are (normally) verbs, followed by what they will be applied to in parentheses:

R essentials

– Packages are installed with the install.packages function and loaded with the library function, once per session:

Packages

library(tidyverse)

Packages

library(tidyverse)

tidyverse

– The tidyverse is a collection of R packages designed for data science.

– All packages share an underlying philosophy and a common grammar.

GitHub: Version control

GitHub Commands: Pull Commit Push

Errors

– Golden Rule: Look for the word Error:

– Server Error: To many files open ….

ae-01

Quarto

– an open-source scientific and technical publishing system

– publish high-quality articles, reports, presentations, websites, blogs, and books in HTML, PDF, MS Word, ePub, and more

– Code goes in chunks, defined by three backticks, narrative goes outside of chunks

How will we use Quarto?

– Every assignment / lab / project will be given to you as a Quarto document

– You will always have a Quarto template document to start with

– As we get more familiar with R, the more code you will construct on your own

The process

You have a data set you want to work with…

mtcars

The process

mtcars

You want to create a visualization. The first thing we need to do is set up the canvas…

The process

mtcars |>
ggplot()

The process

    mtcars |>
        ggplot(
        aes(
             x = variable.name, y = variable.name)
               )

aes: describe how variables in the data are mapped to your canvas

The process

+ “and”

When working with ggplot functions, we will add to our canvus using +

The process

    mtcars |>
        ggplot(
        aes(
             x = variable.name, y = variable.name)
               ) +
        geom_point()

The process

ae-01

Wrap up

– What is version control? Why is it important?

– What is R vs RStudio?

– What is Quarto?