Number of Sample Mean Salary Sample Standard Deviation
Professors (in 1000s) (in $1000)
English 32 71.4 10
Statistics 38 76.9 12.3
A. Are the assumptions for testing to compare two population means satisfied in this case?
Yes, the assumptions for testing are satisfied because both sample sizes are large enough.
No, the assumptions for testing are not satisfied because we were not told that both samples come from normal distribution.
Yes, the assumptions for testing are satisfied because annual salaries are always normally distributed regardless of the sample size.
No, the assumptions for testing are not satisfied because the sample sizes are not large enough.
B. We would like to test whether the average salary of English professors is lower than that of Statistics professors using a = 0.05 level of
significance. Let 1 = English professors, 2 = Statistics professors. Choose the appropriate hypotheses below.
Ο Ηο: μι - με = 0,
Ο Ηο: μι - με = 0,
Ο Ηο: μι - με <0,
Ο Ηο: μι - με = 0,
Ηο: μι- με > 0,
Ηο: μι-με≠ 0,
Ο Ηο: μι - μ2 = 0,
Ο Ηο: μι - με = 0,
Ηα: μι-με > 0
Ηα: μι-με < 0
Ηα: μι- μ2 = 0
Ηα: μι -42≠0
Ηα: μι-με = 0
Ha: 41-42 = 0
Ηα: μι-με≤ 0
Ηα: μι-με ≥ 0