Reference no: EM131005564
Several retired bicycle racers are coaching a large group pf young prospects. They randomly select 7 of their riders to take part in a test of effectiveness of a new diatary supplement that supposed to increase strenght and stamina. Each of 7 does a time trial on the same course. Then they all take the dietary supplement for 4 weeks. At the end of 4 weeks these riders do anither time trial on the same course. The times in minutes recoded by each rider for the trials shown in the following table.
Before 104, 97, 115, 95, 102, 96, 110After 100, 95, 100, 102, 98, 91, 101
a. Construct a 99% confidence interval for mean Ud of the population paired differences where a paired difference is equal to score of an employee before attending course minus the score of the same employee after attending course.
b. Test at 1% significance level whether course increases the mean score of employees. Assume that population of paired differances has normal distribution.