Introducing Spearman’s Coefficient

  • This task introduces Spearman’s coefficient of ranked correlation, as a tool to solve the problem of making quantitative comparisons between pairs of rankings. Students are presented with a list of the ’10 best jokes’ from the Edinburgh Fringe (as voted for by a set of 2000 viewers of the Dave TV channel.)
  • Students make their own ranked list of the jokes, and compare this to the published results – first informally, and then by calculating Spearman’s coefficient.



Prior Knowledge

Students will not need any specific prior knowledge beyond the informal ideas of correlation that should be familiar from GCSE mathematics.

Relevance to Core Maths Qualifications

  • AQA
  • C&G
  • Eduqas
  • Pearson/ Edexcel
  • OCR

Suggested Approaches

Work through the PowerPoint presentation supplied, using the notes provided to lead whole-class and individual questioning and discussion. The activities in this task are suitable for a variety of approaches, including individual work, paired work, and whole class discussion.


The supplied PowerPoint presentation includes extensive notes that address the key teaching points for an introductory lesson on this topic. 

Relevant Digital Technologies

Students could use spreadsheets to perform the required calculations; however it is important to make sense of the formula and calculate some cases ‘by hand’.

Possible Extensions

  • The work presented here could be extended to include determination of ranks from raw data, and dealing with the case of tied ranks.
  • You may wish to present simple (sketched) scatter diagrams to provide a visual image for the different types and values of correlation in the lesson.