Basic stacked bars
When we made the pie and waffle charts in the last exercises, we looked at all years in the data combined together.
Now, we're interested in looking at these patterns over time. To do this we will make a stacked bar chart with the x-axis being the year of observation. Like we did with the pie chart before, we will simplify the data to just be measles, mumps, and other.
Do you notice anything funky in the data after visualizing it this way?
This exercise is part of the course
Visualization Best Practices in R
Exercise instructions
- Modify the
aes()
call to include the year mapped to the x-axis. - Make bars fill the entire y-axis by adjusting
position
argument ingeom_col()
.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
disease_counts <- who_disease %>%
mutate(disease = ifelse(disease %in% c('measles', 'mumps'), disease, 'other')) %>%
group_by(disease, year) %>% # note the addition of year to the grouping.
summarise(total_cases = sum(cases))
# add the mapping of year to the x axis.
ggplot(disease_counts, aes(___, y = total_cases, fill = disease)) +
# Change the position argument to make bars full height
geom_col(___)