Exercise 4: Test your knowledge
After working through Exercise 4, you’ll…
- be able to see a graph and recreate it with
ggplot2 - be able to see a problem and customize a plot with
dplyr&ggplot2to solve it
First, load the WoJ (World of Journalism) dataset from the tidycomm package. Install tidycomm if you haven’t already and then assign the WoJ dataset in its own R object:
If you want help to solve this exercise, here’s a step-by-step tutorial that I’ve created for you:
Task 1
Try creating your own scatter plot. First, load tidyverse to access ggplot2 for data visualization:
Show how journalists’ work experience (work_experience) is associated with their trust in politicians (trust_politicians). To do this, create a very basic scatter plot using ggplot2 and the respective ggplot() function. Use the aes() function inside ggplot() to map variables to the visual properties. Use geom_point() to add points to the plot.
Task 2
Do more experienced journalists become less trusting in politicians? Add this code to your plot to create a regression line:
+ geom_smooth(method = lm, se = FALSE).
What can you conclude from the regression line?
Task 3
Does the relationship between work experience and trust in politicians remain stable across different countries? Alternatively, does work experience influence trust in politicians differently depending on the specific country context?
Try to create a visualization to answer this question using facet_wrap().
Task 4
In your current visualization, it may be challenging to discern cross-country differences. Let’s aim to create a visualization that illustrates these differences across countries more distinctly.
Remove the facet_wrap() and the geom_point() code line. This leaves you with this graph:
Now, display every country in a separate color by using the color argument inside the aes() function.
Task 5
Add fitting labels to your plot. For example, set the main title to display: “Impact of Work Experience on Trust in Politicians”. The x-axis label should read “Years of Work Experience in Journalism”, and the y-axis label should read “Trust in Politicians on a 5-point Likert Scale”. The label for the color legend should be “Country”.