This data set contains the number of errors detected in a set of bills and the name of the person in charge of the bill.
data("ss.data.bills")Format
A data frame with 32 observations on the following 3 variables.
- nbill
a numeric vector identifying a given bill
- clerk
a character vector for the clerk responsible for the bill
- errors
a character vector with the number of errors in the bill
Source
Table 6.1 in the reference below.
Details
This data set illustrates concepts in the book ``Quality Control with R''.
References
Cano, E.L. and Moguerza, J.M. and Prieto Corcoba, M. (2015) Quality Control with R. An ISO Standards Approach. Springer.
Examples
data(ss.data.bills)
str(ss.data.bills)
#> 'data.frame': 32 obs. of 3 variables:
#> $ nbill : int 1 2 3 4 5 6 7 8 9 10 ...
#> $ clerk : chr "Mary" "Mary" "John" "John" ...
#> $ errors: int 2 2 0 1 2 0 0 0 0 1 ...
barplot(table(ss.data.bills$clerk),
main = "number of invoices")
aggregate(errors ~ clerk, ss.data.bills, sum)
#> clerk errors
#> 1 John 13
#> 2 Mary 10