Automobile dealers classified according to type dealership and service rendered to customers

Data for Example 2.22

Dealers

Format

A data frame/tibble with 122 observations on two variables

type

a factor with levels Honda, Toyota, Mazda, Ford, Dodge, and Saturn

service

a factor with levels Replaces unnecessarily and Follows manufacturer guidelines

References

Kitchens, L. J. (2003) Basic Statistics and Data Analysis. Pacific Grove, CA: Brooks/Cole, a division of Thomson Learning.

Examples

xtabs(~type + service, data = Dealers)
#>         service
#> type     Replaces unnecessarily Follows manufacturer guidelines
#>   Honda                      19                               2
#>   Toyota                      3                              16
#>   Mazda                      12                               9
#>   Ford                        8                              13
#>   Dodge                      11                              10
#>   Saturn                      4                              15
T1 <- xtabs(~type + service, data = Dealers)
T1
#>         service
#> type     Replaces unnecessarily Follows manufacturer guidelines
#>   Honda                      19                               2
#>   Toyota                      3                              16
#>   Mazda                      12                               9
#>   Ford                        8                              13
#>   Dodge                      11                              10
#>   Saturn                      4                              15
addmargins(T1)
#>         service
#> type     Replaces unnecessarily Follows manufacturer guidelines Sum
#>   Honda                      19                               2  21
#>   Toyota                      3                              16  19
#>   Mazda                      12                               9  21
#>   Ford                        8                              13  21
#>   Dodge                      11                              10  21
#>   Saturn                      4                              15  19
#>   Sum                        57                              65 122
pt <- prop.table(T1, margin = 1)
pt
#>         service
#> type     Replaces unnecessarily Follows manufacturer guidelines
#>   Honda               0.9047619                       0.0952381
#>   Toyota              0.1578947                       0.8421053
#>   Mazda               0.5714286                       0.4285714
#>   Ford                0.3809524                       0.6190476
#>   Dodge               0.5238095                       0.4761905
#>   Saturn              0.2105263                       0.7894737
barplot(t(pt),  col = c("red", "skyblue"), legend = colnames(T1))

rm(T1, pt)