Module #9 Assignment

 1.

Your data.frame is

> assignment_data <- data.frame( Country = c("France","Spain","Germany","Spain","Germany", "France","Spain","France","Germany","France"), age = c(44,27,30,38,40,35,52,48,45,37), salary = c(6000,5000,7000,4000,8000), Purchased=c("No","Yes","No","No","Yes", "Yes","No","Yes","No","Yes"))

Generate simple table in R that consists of four rows: Country, age, salary and purchased.

In order to make a table from the dataframe, I loaded the data.table package. This is the result:

> setDT(assignment_data)
> assignment_data
    Country age salary Purchased
 1:  France  44   6000        No
 2:   Spain  27   5000       Yes
 3: Germany  30   7000        No
 4:   Spain  38   4000        No
 5: Germany  40   8000       Yes
 6:  France  35   6000       Yes
 7:   Spain  52   5000        No
 8:  France  48   7000       Yes
 9: Germany  45   4000        No
10:  France  37   8000       Yes

2. Generate contingency table also know as rx C table using mtcars dataset.

>assignment9 <- table(mtcars$gear, mtcars$cyl, dnn=c("gears"

 assignment9 <- table(mtcars$gear, mtcars$cyl, dnn=c("gears", "cyl"))
> print(assignment9)                                                    
     cyl
gears  4  6  8
    3  1  2 12
    4  8  4  0
    5  2  1  2

2.1 Add the addmargins() function to report on the sum totals of the rows and columns of assignment9 table
>addmargins(assignment9)

> tablea <- addmargins(assignment9)                     
> tablea
     cyl
gears  4  6  8 Sum
  3    1  2 12  15
  4    8  4  0  12
  5    2  1  2   5
  Sum 11  7 14  32

2.2 Add prop.tables() function, and report on the proportional weight of each value in a assignment9 table

tableb <- prop.table(assignment9)
> tableb
     cyl
gears       4       6       8
    3 0.03125 0.06250 0.37500
    4 0.25000 0.12500 0.00000
    5 0.06250 0.03125 0.06250

2.3 Add margin = 1 to the argument under prop.table() function, and report on the row proportions found in assignment9 table.

tablec <- prop.table(assignment9, margin = 1)
> print(tablec)
     cyl
gears          4          6          8
    3 0.06666667 0.13333333 0.80000000
    4 0.66666667 0.33333333 0.00000000
    5 0.40000000 0.20000000 0.40000000