Lecture 3
Duke University
STA 199 - Spring 2024
2024-01-23
Questions from the prepare materials?
Questions from the prepare materials?
Is there any code in the videos that is not in the readings? Yes and no. There is no substantial functionality introduced in the videos that is not also in the readings, however the examples in the videos are different than the ones in the reading.
What are all of the geom
s we need to know? You don’t need to “memorize” or even “know” all o the geoms available in the ggplot2 package, but you can find a list of them on the ggplot2 cheat sheet or on the reference page.
Could you please clarify what situations it would be appropriate to use each geom function? Today’s topic! And think about it as “what plot should I make for which type of variable”.
ae
repo for each application exercise this week.ae-02-bechdel-dataviz
If you were in class last Thursday:
and followed along with the application exercise…
Go to the project navigator in RStudio (top right corner of your RStudio window) and open the project called ae
. If there are any uncommitted files, commit them so you can start with a clean slate.
If you missed class last Thursday:
or didn’t follow along with the application exercise…
Go to the course GitHub org and find your ae
repo. Clone the repo in your container, open the Quarto document called ae-02-bechdel
.
ggplot()
.+
s.color = binary
vs. color = "pink"
.facet_wrap()
when faceting (creating small multiples) by one variable and facet_grid()
when faceting by two variables.What do these three plots show?
penguins
# A tibble: 344 × 8
species island bill_length_mm bill_depth_mm flipper_length_mm body_mass_g sex year
<fct> <fct> <dbl> <dbl> <int> <int> <fct> <int>
1 Adelie Torgers… 39.1 18.7 181 3750 male 2007
2 Adelie Torgers… 39.5 17.4 186 3800 fema… 2007
3 Adelie Torgers… 40.3 18 195 3250 fema… 2007
4 Adelie Torgers… NA NA NA NA <NA> 2007
5 Adelie Torgers… 36.7 19.3 193 3450 fema… 2007
6 Adelie Torgers… 39.3 20.6 190 3650 male 2007
7 Adelie Torgers… 38.9 17.8 181 3625 fema… 2007
8 Adelie Torgers… 39.2 19.6 195 4675 male 2007
9 Adelie Torgers… 34.1 18.1 193 3475 <NA> 2007
10 Adelie Torgers… 42 20.2 190 4250 <NA> 2007
# ℹ 334 more rows
Analyzing a single variable:
Numerical: histogram, box plot, density plot, etc.
Categorical: bar plot, pie chart, etc.
Analyzing the relationship between two variables:
Numerical + numerical: scatterplot
Numerical + categorical: side-by-side box plots, violin plots, etc.
Categorical + categorical: stacked bar plots
Using an aesthetic (e.g., fill, color, shape, etc.) or facets to represent the second variable in any plot