Introduction

• In previous chapters, we learned to plot one to two variables on a single graph
• Here, we are looking at the Salaries data from the carData package

library(pacman)
p_load(ggplot2, dplyr) 

data(Salaries, package="carData")

ggplot(Salaries, aes(x=yrs.since.phd,
                     y=salary)) + 
  geom_point() + 
  labs(title="Academic salary by years since degree")

• What if we want to visualize more than two variables?
• The Salaries data set has multiple columns we can plot

Salaries %>% head()

##        rank discipline yrs.since.phd yrs.service  sex salary
## 1      Prof          B            19          18 Male 139750
## 2      Prof          B            20          16 Male 173200
## 3  AsstProf          B             4           3 Male  79750
## 4      Prof          B            45          39 Male 115000
## 5      Prof          B            40          41 Male 141500
## 6 AssocProf          B             6           6 Male  97000