Edexcel Paper 3 2022 June — Question 6

Exam BoardEdexcel
ModulePaper 3 (Paper 3)
Year2022
SessionJune
TopicHypothesis test of Pearson’s product-moment correlation coefficient

6. Anna is investigating the relationship between exercise and resting heart rate. She takes a random sample of 19 people in her year at school and records for each person
  • their resting heart rate, \(h\) beats per minute
  • the number of minutes, \(m\), spent exercising each week
Her results are shown on the scatter diagram.
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  1. Interpret the nature of the relationship between \(h\) and \(m\) Anna codes the data using the formulae $$\begin{aligned} & x = \log _ { 10 } m
    & y = \log _ { 10 } h \end{aligned}$$ The product moment correlation coefficient between \(x\) and \(y\) is - 0.897
  2. Test whether or not there is significant evidence of a negative correlation between \(x\) and \(y\)
    You should
    • state your hypotheses clearly
    • use a \(5 \%\) level of significance
    • state the critical value used
    The equation of the line of best fit of \(y\) on \(x\) is $$y = - 0.05 x + 1.92$$
  3. Use the equation of the line of best fit of \(y\) on \(x\) to find a model for \(h\) on \(m\) in the form $$h = a m ^ { k }$$ where \(a\) and \(k\) are constants to be found.