Import data

# excel file
data <- read_excel("../00_data/Salaries.xlsx")
data
## # A tibble: 397 × 6
##    rank      discipline yrs.since.phd yrs.service sex    salary
##    <chr>     <chr>              <dbl>       <dbl> <chr>   <dbl>
##  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
##  7 Prof      B                     30          23 Male   175000
##  8 Prof      B                     45          45 Male   147765
##  9 Prof      B                     21          20 Male   119250
## 10 Prof      B                     18          18 Female 129000
## # ℹ 387 more rows

State one question

What is the correlation between years since phd and years of service?

Plot data

ggplot(data = data) + 
    geom_point(mapping = aes(x = yrs.service, y = yrs.since.phd))

Interpret

It seems to be that there is almost a direct correlation with years of service and years since phd, as the plot has formed a line upwards and to the right with few points straying from the line.