State two conditions under which it might be more appropriate to use Spearman’s rank correlation coefficient rather than the product moment correlation coefficient.
A researcher took a random sample of 12 luxury watches from a boutique. The price, in pounds, and the age, in years, of each watch were recorded.
The Spearman’s rank correlation coefficient between the results was calculated as rs=−0.598r_s = -0.598rs=−0.598.
Test, at the 5% level of significance, whether or not there is evidence of a correlation. State clearly your hypotheses and the critical value used.
The product moment correlation coefficient (PMCC) between the results was calculated as r=−0.482r = -0.482r=−0.482.
Test, at the 5% level of significance, whether or not there is evidence of a negative correlation. State clearly your hypotheses and the critical value used.
278 exam-style questions on CCEA A Level Maths 2.5 Data presentation and interpretation, covering 2.5.1 Data presentation and interpretation, 2.5.2 Data presentation and interpretation, 2.5.3 Data presentation and interpretation, 2.5.4 Data presentation and interpretation, 2.5.5 Data presentation and interpretation, 2.5.6 Data presentation and interpretation, 2.5.7 Data presentation and interpretation, 2.5.8 Data presentation and interpretation, 2.5.9 Data presentation and interpretation, and 2.5 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.