Exercise

# Did the 2015 event have this problem?

You would like to know if this is a typical problem with pools in competitive swimming. To address this question, perform a similar analysis for the results of the 2015 FINA World Championships. That is, compute the mean fractional improvement for going from lanes 1-3 to lanes 6-8 for the 2015 competition, along with a 95% confidence interval on the mean. Also test the hypothesis that the mean fractional improvement is zero.

The arrays `swimtime_low_lanes_15`

and `swimtime_high_lanes_15`

have the pertinent data.

Instructions

**100 XP**

- Compute the fractional improvement,
`f`

using the arrays`swimtime_low_lanes_15`

and`swimtime_high_lanes_15`

. Also compute the mean of`f`

, storing it as`f_mean`

. - Draw 10,000 bootstrap replicates of the mean
`f`

. - Compute the 95% confidence interval of the mean fractional improvement.
- Shift
`f`

to create`f_shift`

such that its mean is zero. - Draw 100,000 bootstrap replicates of the mean of
`f_shift`

. - Compute the p-value.