Speedy Swift is a package delivery service that serves the greater Atlanta, Georgia, metropolitan area. To maintain customer loyalty, one of Speedy Swift's performance objectives is on-time delivery. To monitor its performance, each delivery is measured on the following scale: early (package delivered before the promised time), on-time (package delivered within 15 minutes of the promised time), late (package delivered more than 15 minutes past the promised time), or lost (package never delivered). Speedy Swift's objective is to deliver 99% of all packages either early or on-time.
Speedy collected the following data for last month's performance:
On-time On-time Early Late On-time On-time On-time On-time Late On-time
Early On-time On-time Early On-time On-time On-time On-time On-time On-time
Early On-time Early On-time On-time On-time Early On-time On-time On-time
Early On-time On-time Early Early Early On-time Loss On-time Early
Late Late Late On-time On-time On-time On-time On-time On-time On-time
On-time Late Early On-time Early On-time Lost On-time On-time On-time
Early Early On-time On-time Late Early Early On-time On-time On-time
On-time On-time Early On-time Early On-time Early On-time Late On-time
On-time Early On-time On-time On-time Late On-time Lost On-time On-time
On-time On-time On-time On-time On-time Early Early On-time On-time On-time
(a) What scale is used to measure delivery performance? What kind of variable is delivery performance?
(b) Construct a frequency table for delivery performance for last month.
(c) Construct a relative frequency table for delivery performance last month.