Scatter plots (geom_point) in R Programming - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of geom_point() in R's ggplot2?

geom_point() adds points to a plot, creating a scatter plot that shows the relationship between two continuous variables.

beginner

How do you specify the x and y variables in a scatter plot using ggplot2?

You specify them inside aes() as x = variable1 and y = variable2 when creating the plot.

intermediate

What happens if you add color inside aes() in geom_point()?

Points are colored based on the values of the variable mapped to color, helping to show groups or categories.

beginner

How can you change the size of points in a scatter plot?

You can set the size argument inside geom_point() to a number to make points bigger or smaller.

beginner

Why is a scatter plot useful in data analysis?

It helps you see patterns, trends, or relationships between two numeric variables visually.

What does geom_point() do in ggplot2?

A Creates a scatter plot by adding points

B Creates a bar chart

C Adds a line to the plot

D Removes points from the plot

geom_point() adds points to create scatter plots showing relationships between variables.

Where do you specify which variables go on the x and y axes in ggplot2?

A Inside <code>aes()</code> function

B Inside <code>geom_point()</code> size argument

C In the <code>labs()</code> function

D In the <code>theme()</code> function

The aes() function maps variables to axes and other aesthetics.

How do you color points by a category in a scatter plot?

A Use <code>size</code> argument

B Map the category variable to <code>color</code> inside <code>aes()</code>

C Set <code>color</code> outside <code>aes()</code> to a variable

D Use <code>fill</code> argument inside <code>geom_point()</code>

Mapping a variable to color inside aes() colors points by that variable.

Which argument changes the size of points in geom_point()?

A alpha

B color

C size

D shape

The size argument controls how big or small the points appear.

What kind of variables are best visualized with scatter plots?

A Only one variable

B Two categorical variables

C One numeric and one categorical variable

D Two numeric continuous variables

Scatter plots show relationships between two numeric continuous variables.

Explain how to create a basic scatter plot using ggplot2 and geom_point().

Think about how you tell ggplot which data to use and which variables go on the axes.

Describe how you can use color and size to add more information to a scatter plot.

Consider how different point colors or sizes can show categories or importance.