Import data

# csv file
data <- read_csv("../00_data/Salaries.csv")
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
# excel file
# data <- read_excel("../00_data/Salaries.xlsx")
# data

Apply the following dplyr verbs to your data

Filter rows

filter(data, rank == "Prof", salary >= 10000)
## # A tibble: 266 × 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 Prof  B                     45          39 Male   115000
##  4 Prof  B                     40          41 Male   141500
##  5 Prof  B                     30          23 Male   175000
##  6 Prof  B                     45          45 Male   147765
##  7 Prof  B                     21          20 Male   119250
##  8 Prof  B                     18          18 Female 129000
##  9 Prof  B                     20          18 Male   104800
## 10 Prof  B                     12           3 Male   117150
## # ℹ 256 more rows
filter(data, rank == "Prof" | rank == "AsstProf")
## # A tibble: 333 × 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 Prof     B                     30          23 Male   175000
##  7 Prof     B                     45          45 Male   147765
##  8 Prof     B                     21          20 Male   119250
##  9 Prof     B                     18          18 Female 129000
## 10 AsstProf B                      7           2 Male    79800
## # ℹ 323 more rows

Arrange rows

arrange(data, desc(yrs.since.phd))
## # A tibble: 397 × 6
##    rank      discipline yrs.since.phd yrs.service sex   salary
##    <chr>     <chr>              <dbl>       <dbl> <chr>  <dbl>
##  1 Prof      A                     56          57 Male   76840
##  2 Prof      B                     56          49 Male  186960
##  3 Prof      A                     54          49 Male   78162
##  4 Prof      A                     52          48 Male  107200
##  5 Prof      A                     51          51 Male   57800
##  6 AssocProf A                     49          49 Male   81800
##  7 Prof      A                     49          43 Male   72300
##  8 Prof      B                     49          60 Male  192253
##  9 Prof      A                     49          40 Male   88709
## 10 AssocProf B                     48          53 Male   90000
## # ℹ 387 more rows

Select columns

select(data, sex)
## # A tibble: 397 × 1
##    sex   
##    <chr> 
##  1 Male  
##  2 Male  
##  3 Male  
##  4 Male  
##  5 Male  
##  6 Male  
##  7 Male  
##  8 Male  
##  9 Male  
## 10 Female
## # ℹ 387 more rows

Add columns

mutate(data,"years_phd-service" = yrs.since.phd - yrs.service)
## # A tibble: 397 × 7
##    rank    discipline yrs.since.phd yrs.service sex   salary `years_phd-service`
##    <chr>   <chr>              <dbl>       <dbl> <chr>  <dbl>               <dbl>
##  1 Prof    B                     19          18 Male  139750                   1
##  2 Prof    B                     20          16 Male  173200                   4
##  3 AsstPr… B                      4           3 Male   79750                   1
##  4 Prof    B                     45          39 Male  115000                   6
##  5 Prof    B                     40          41 Male  141500                  -1
##  6 AssocP… B                      6           6 Male   97000                   0
##  7 Prof    B                     30          23 Male  175000                   7
##  8 Prof    B                     45          45 Male  147765                   0
##  9 Prof    B                     21          20 Male  119250                   1
## 10 Prof    B                     18          18 Fema… 129000                   0
## # ℹ 387 more rows

Summarize by groups

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
#avg years_phd-service
data |> 
  filter(sex == "Male") |> 
  summarise(`years_phd-service` = mean(yrs.since.phd - yrs.service))
## # A tibble: 1 × 1
##   `years_phd-service`
##                 <dbl>
## 1                4.67