Chapter 2 Heatmap

You should use this method if the data is:

• Categorical

In this chapter you will learn how to do some simple data explorations for categorical variables using heatmaps with the function geom_bin2d()

Basic plot:

wage_df %>%
  ggplot(aes(jobclass, education)) +
  geom_bin2d() +
  scale_fill_gradient(low = "gray85", high = "steelblue") 

Plot with some adjustments:

wage_df %>%
  ggplot(aes(jobclass, education)) +
  geom_bin2d(binwidth = c(1, 1), alpha = 0.8) +
  theme_classic() + 
  scale_fill_gradient(low = "gray85", high = "steelblue") +
  labs(fill = "number of \n workers", y = "Education", x = "Job class")