An experiment is designed to compare the average salaries of employees in a particular position in two competing companies. The null hypothesis is assumed to be that there is no difference in the average salaries of employees in a particular position in the two companies. What is the alternative hypothesis?
A.
There is a difference in the average salaries that is equal to the standard deviation.
B.
There is no difference in the average salaries.
C.
There is a difference in the average salaries.
D.
The average salaries are equal.
Answers
Answer:
If the null hyp. assumes equal average salaries (i.e. no difference), then the alternative can take on three cases: (1) one mean is greater than the other, (2), one mean is small than the other, or (3) the means are not equal. (1) and (2) sound the same, so I should be more precise. If μ1 is supposed to be the average for one company, and μ2 the average for the other, then (1) would indicate μ1>μ2, while (2) would represent the case that μ1<μ2.
or
The alternative hypothesis is there is a (significant) difference between the average salaries of employees in the two companies.
The alternative hypothesis is the hypothesis that is validated when the null hypothesis fails to be supported.
THEREFORE THE ANSWER IS (C).