On a given day, the proportion of workers from Company B who purchase a coffee from the company cafeteria is 0.62 and the propor
tion of workers from Company C who purchase a coffee from the company cafeteria is 0.71. A random sample of40 workers was selected from Company B and another random sample of 40 workers was selected from Company C. The proportion of workers from Company B who purchased coffee was pˆB=0.70 and the proportion of workers from Company C who purchased coffee was pˆC=0.75. What is the correct unit of measure for the mean of the sampling distribution of pˆB−pˆC ?
The sampling distribution of the mean will have no unit.
Explanation:
Given that:
P(B) = 0.62
P(C) = 0.71
pˆB = 0.70
pˆC = 0.75
The expression : pˆB−pˆC
Represents the difference in mean of the sample distribution :
The proportions pˆB = 0.70 and pˆC = 0.75 are obtained as (number of workers who purchased coffee / total number of workers). The ratio above due to division will have no units.
