Edexcel S1 2016 June — Question 1

Exam BoardEdexcel
ModuleS1 (Statistics 1)
Year2016
SessionJune
TopicLinear regression
TypeCalculate y on x from raw data table

  1. A biologist is studying the behaviour of bees in a hive. Once a bee has located a source of food, it returns to the hive and performs a dance to indicate to the other bees how far away the source of the food is. The dance consists of a series of wiggles. The biologist records the distance, \(d\) metres, of the food source from the hive and the average number of wiggles, \(w\), in the dance.
Distance, \(\boldsymbol { d } \mathbf { m }\)305080100150400500650
Average number
of wiggles, \(\boldsymbol { w }\)
0.7251.2101.7752.2503.5186.3828.1859.555
[You may use \(\sum w = 33.6 \sum d w = 13833 \mathrm {~S} _ { d d } = 394600 \mathrm {~S} _ { w w } = 80.481\) (to 3 decimal places)]
  1. Show that \(\mathrm { S } _ { d w } = 5601\)
  2. State, giving a reason, which is the response variable.
  3. Calculate the product moment correlation coefficient for these data.
  4. Calculate the equation of the regression line of \(w\) on \(d\), giving your answer in the form \(w = a + b d\) A new source of food is located 350 m from the hive.
    1. Use your regression equation to estimate the average number of wiggles in the corresponding dance.
    2. Comment, giving a reason, on the reliability of your estimate.