Exercise 22. Two smooth density plots 3

We can also assign groups using the fill argument. When using the geom_density geometry, color creates a colored line for the smooth density plot while fill colors in the area under the curve.

We can see what this looks like by running the following code:

heights %>% 
  ggplot(aes(height, fill = sex)) + 
  geom_density()

However, here the second density is drawn over the other. We can change this by using something called alpha blending.

Set the alpha parameter to 0.2 in the geom_density function to make this change.