AQA Further Paper 3 Statistics 2020 June — Question 8

Exam BoardAQA
ModuleFurther Paper 3 Statistics (Further Paper 3 Statistics)
Year2020
SessionJune
TopicChi-squared distribution

8 Ray is conducting a hypothesis test with the hypotheses
\(\mathrm { H } _ { 0 }\) : There is no association between time of day and number of snacks eaten
\(\mathrm { H } _ { 1 }\) : There is an association between time of day and number of snacks eaten
He calculates expected frequencies correct to two decimal places, which are given in the following table.
Number of snacks eaten
\cline { 2 - 5 }\cline { 2 - 4 }012 or more
\cline { 2 - 4 } Time of Day23.6821.055.26
\cline { 2 - 5 }Night21.3218.954.74
\cline { 2 - 5 }
\cline { 2 - 5 }
Ray calculates his test statistic using \(\sum \frac { ( O - E ) ^ { 2 } } { E }\)
8
  1. State, with a reason, the error Ray has made and describe any changes Ray will need to make to his test.
    8
  2. Having made the necessary corrections as described in part (a), the correct value of the test statistic is 8.74 Complete Ray's hypothesis test using a \(1 \%\) level of significance.