AQA S1 2014 June — Question 4

Exam BoardAQA
ModuleS1 (Statistics 1)
Year2014
SessionJune
TopicBivariate data
TypeCalculate r from summary statistics

4 Every year, usually during early June, the Isle of Man hosts motorbike races. Each race consists of three consecutive laps of the island's course. To compete in a race, a rider must first complete at least one qualifying lap. The data refer to the lightweight motorbike class in 2012 and show, for each of a random sample of 10 riders, values of $$u = x - 100 \quad \text { and } \quad v = y - 100$$ where
\(x\) denotes the average speed, in mph, for the rider's fastest qualifying lap and
\(y\) denotes the average speed, in mph, for the rider's three laps of the race.
\cline { 2 - 11 } \multicolumn{1}{c|}{}Rider
\cline { 2 - 11 } \multicolumn{1}{c|}{}\(\mathbf { A }\)\(\mathbf { B }\)\(\mathbf { C }\)\(\mathbf { D }\)\(\mathbf { E }\)\(\mathbf { F }\)\(\mathbf { G }\)\(\mathbf { H }\)\(\mathbf { I }\)\(\mathbf { J }\)
\(\boldsymbol { u }\)7.8813.024.292.886.267.033.6011.7813.1511.69
\(\boldsymbol { v }\)6.6310.163.630.475.708.013.307.3113.0811.82
    1. Calculate the value of \(r _ { u v }\), the product moment correlation coefficient between \(u\) and \(v\).
    2. Hence state the value of \(r _ { x y }\), giving a reason for your answer.
  1. Interpret your value of \(r _ { x y }\) in the context of this question.