OCR Further Statistics AS Specimen — Question 8

Exam BoardOCR
ModuleFurther Statistics AS (Further Statistics AS)
SessionSpecimen
TopicHypothesis test of Pearson’s product-moment correlation coefficient

8 The following table gives the mean per capita consumption of mozzarella cheese per annum, \(x\) pounds, and the number of civil engineering doctorates awarded, \(y\), in the United States in each of 10 years.
\(x\)9.39.79.79.79.910.210.511.010.610.6
\(y\)480501540552547622655701712708
  1. Find the equation of the regression line of \(y\) on \(x\). You are given that the product moment correlation coefficient is 0.959 .
  2. Explain whether this value would be different if \(x\) is measured in kilograms instead of pounds. It is desired to carry out a hypothesis test to investigate whether there is correlation between these two variables.
  3. Assume that the data is a random sample of all years.
    (a) Carry out the test at the \(10 \%\) significance level.
    (b) Explain whether your conclusion suggests that manufacturers of mozzarella cheese could increase consumption by sponsoring doctoral candidates in civil engineering. {www.ocr.org.uk}) after the live examination series. If OCR has unwittingly failed to correctly acknowledge or clear any third-party content in this assessment material, OCR will be happy to correct its mistake at the earliest possible opportunity. For queries or further information please contact the Copyright Team, First Floor, 9 Hills Road, Cambridge CB2 1GE.
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