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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.