Edexcel S1 2014 June — Question 3

Exam BoardEdexcel
ModuleS1 (Statistics 1)
Year2014
SessionJune
TopicLinear regression
TypeCalculate y on x from raw data table

3. The table shows data on the number of visitors to the UK in a month, \(v\) (1000s), and the amount of money they spent, \(m\) ( \(\pounds\) millions), for each of 8 months.
Number of visitors
\(v ( 1000 \mathrm {~s} )\)
24502480254024202350229024002460
Amount of money spent
\(m ( \pounds\) millions \()\)
13701350140013301270121013301350
You may use
\(S _ { v v } = 42587.5 \quad S _ { v m } = 31512.5 \quad S _ { m m } = 25187.5 \quad \sum v = 19390 \quad \sum m = 10610\)
  1. Find the product moment correlation coefficient between \(m\) and \(v\).
  2. Give a reason to support fitting a regression model of the form \(m = a + b v\) to these data.
  3. Find the value of \(b\) correct to 3 decimal places.
  4. Find the equation of the regression line of \(m\) on \(v\).
  5. Interpret your value of \(b\).
  6. Use your answer to part (d) to estimate the amount of money spent when the number of visitors to the UK in a month is 2500000
  7. Comment on the reliability of your estimate in part (f). Give a reason for your answer.