Plotting

Learning outcomes

• I am comfortable with the first chapter of R for Data Science
• I can use ggplot2 to create a simple plot
• I can save a plot created by ggplot2
• I can tell what ggplot2 aesthetics are
• I can tell what ggplot2 geometrical objects are

For teachers

Teaching goals are:

• Learners have read part of the first chapter of R for Data Science
• Learners have created simple plots in ggplot2
• Learners can create simple ggplots from tidy data
• Learners can set the aesthetics x, y and color
• Learners can use geom_scatter, geom_boxplot and geom_smooth for simple aesthetics

Prior question:

• What is the most used use R package for plotting?
• What is gg in ggplot2?
• What is tidy data?
• There is a philosophy that 'missing values should never silently go missing'. What does that mean?

Feedback questions:

• What is gg in ggplot2?
• What is tidy data?
• What is an aesthetic?
• What is a geom?
• The philosophy that 'missing values should never silently go missing'. What does this mean?

Why ggplot2 is important

ggplot2 allows you to create publication-quality graphs for your paper, using a unified (and extensible) grammar, which allows you to express your unique plotting needs.

Additionally, ggplot2 is the CRAN package with the most downloads per month.

Exercises

Exercise 1: your first ggplot2 plots

• Read R for data science, chapter 1 until the exercises of 1.2.5
• Do all exercises of 1.2.5

Answers

See the answers here

Note that the answers use chapter 2.2.5.

Exercise 2: saving your plots

• Read R for data science, chapter 1 until the exercises of 1.6.1
• Do all exercises of 1.6.1.

Answers

See the answers here

Note that the answers use chapter 2.6.1.

(optional) Exercise 3: different type of data, different type of plot

• Read R for data science, chapter 1 until the exercises of 1.4.3.
• Do all exercises of 1.4.3

Answers

See the answers here

Note that the answers use chapter 2.4.3.

(optional) Exercise 4: expressing relations in color, fill and facets

• Read R for data science, chapter 1 until the exercises of 1.5.5
• Do all exercises of 1.5.5

Answers

See the answers here

Note that the answers use chapter 2.5.5.