A marine biologist is researching the relationship between the depth, ddd (metres), of a specific reef and the biodiversity index, bbb, of the surrounding ecosystem. Data is collected from 8 distinct locations as shown in the table below.
| Depth ddd (m) | 5 | 12 | 20 | 35 | 45 | 60 | 75 | 90 |
|---|---|---|---|---|---|---|---|---|
| Index bbb | 7.9 | 8.2 | 5.8 | 6.3 | 4.4 | 3.1 | 2.5 | 1.2 |
Calculate the Spearman's rank correlation coefficient between ddd and bbb.
The biologist's initial hypothesis was that there would be no correlation between depth and biodiversity index.
Test, at the 5% level of significance, the biologist's claim. State your hypotheses clearly. (The critical value for sample size n=8n=8n=8 at the 5% two-tailed level is 0.7381).
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.