A consumer agency wanted to investigate if four insurance companies differed with regard to the premiums charged for auto insurance.
The agency randomly selects a few auto drivers who were insured by each of these companies and had similar driving records and Insurance policies.
The following table gives the premiums paid per month by these drives insured by the four insurance companies.
Company A (1): 64 72 54 42
Company B(2): 48 69 87
Company C(3): 57 61 90 77 70
Company D(4): 62 53 46 51
Using the 1% significance level, test whether the mean auto insurance premium paid per month by all drivers is the same.
The nut hypothesis:.............................
SSB".........................
SSW".........................
Test statistic"..........................
Critical value"....................