The turnover (in millions of pounds) for 8 train companies and 8 coach companies are given below.
Train 4.3 13.2 134 88 92 66.5 122.1 102
Coach 2.2 31 44 72 19 89.3 55.9 43.1
(a)Using an appropriate statistical test determine whether train companies or coach companies have higher turnovers. State the test used, your null hypothesis, your conclusion and the evidence you base that conclusion upon.
(b)Find the 99% confidence interval for the train companies’ variation in turnover.
(c) Perform an F test (using α=0.05) to determine whether the difference in variation between train and coach company turnover is significant.