In: Statistics and Probability
Samples of starting annual salaries for individuals entering the public accounting and financial planning professions follow. Annual salaries are shown in thousands of dollars.
Public Accountant | Financial Planner |
---|---|
51.2 | 48.0 |
59.8 | 49.2 |
55.3 | 53.1 |
57.2 | 55.9 |
54.2 | 51.9 |
56.0 | 52.6 |
51.9 | 49.7 |
60.5 | 53.9 |
57.0 | 51.8 |
50.9 | 49.9 |
(a)
Use a 0.05 level of significance and test the hypothesis that there is no difference between the starting annual salaries of public accountants and financial planners.
State the null and alternative hypotheses.
H0: Median salary for public accountants −
Median salary for financial planners ≤ 0
Ha: Median salary for public accountants −
Median salary for financial planners > 0H0:
The two populations of salaries are not identical.
Ha: The two populations of salaries are
identical. H0: The
two populations of salaries are identical.
Ha: The two populations of salaries are not
identical.H0: Median salary for public
accountants − Median salary for financial planners > 0
Ha: Median salary for public accountants −
Median salary for financial planners = 0H0:
Median salary for public accountants − Median salary for financial
planners ≥ 0
Ha: Median salary for public accountants −
Median salary for financial planners < 0
Find the value of the test statistic.
W =
Find the p-value. (Round your answer to four decimal places.)
p-value =
What is your conclusion?
Do not reject H0. There is not sufficient evidence to conclude that there is a significant difference between the starting annual salaries of public accountants and financial planners.Reject H0. There is sufficient evidence to conclude that there is a significant difference between the starting annual salaries of public accountants and financial planners. Do not reject H0. There is sufficient evidence to conclude that there is a significant difference between the starting annual salaries of public accountants and financial planners.Reject H0. There is not sufficient evidence to conclude that there is a significant difference between the starting annual salaries of public accountants and financial planners.
(b)
What are the sample median annual salaries (in $) for the two professions?
Public Accountants sample median = $
Financial Planners sample median = $
a)
H0: The two populations of salaries are identical.
Ha: The two populations of salaries are not identical
sample 1 | sample 2 | rank for sample 1 | rank for sample 2 |
51.2 | 48 | 6 | 1 |
59.8 | 49.2 | 19 | 2 |
55.3 | 53.1 | 14 | 11 |
57.2 | 55.9 | 18 | 15 |
54.2 | 51.9 | 13 | 8.5 |
56 | 52.6 | 16 | 10 |
51.9 | 49.7 | 8.5 | 3 |
60.5 | 53.9 | 20 | 12 |
57 | 51.8 | 17 | 7 |
50.9 | 49.9 | 5 | 4 |
sample 1
sample size , n1 = 10
sum of ranks , R1 = 136.5
sample 2
sample size , n2 = 10
sum of ranks , R2 = 73.5
value of the test statistic,
W=sum of ranks for smaller sample size =
136.5
mean ,µ = n1(n1+n2+1)/2 = 105
std dev,σ = √(n1*n2*(n1+n2+1)/12) =
13.2288
Z-stat = (R - µ)/σ = 2.3812
Z*, Z critical value = 1.960
P-value =
0.0173
Conclusion: P-value<α ,
Reject null hypothesis
Reject H0. There is sufficient evidence to conclude that there is a significant difference between the starting annual salaries of public accountants and financial planners.
b)
Public Accountants sample median =0.5(n+1)th value of sorted data = 5.5th of sorted data = $55.65
Financial Planners sample median = 0.5(n+1)th value of sorted data = 5.5th of sorted data = $51.85