A marine biologist is investigating whether species biodiversity decreases as the depth of a coral reef increases. She maintains a database of 150 identified reef locations in a protected zone and selects a random sample of 8 sites.
Outline how the biologist should select this random sample of 8 sites.
The biologist recorded the maximum depth (hhh meters) of each reef site and ranked the sites according to their Biodiversity Index (BBB), where 1 represents the highest biodiversity and 8 represents the lowest biodiversity. The results are shown in the table below:
| Site | A | B | C | D | E | F | G | H |
|---|---|---|---|---|---|---|---|---|
| Depth hhh (m) | 54 | 12 | 33 | 45 | 8 | 22 | 60 | 28 |
| Biodiversity Rank BBB | 8 | 2 | 5 | 7 | 1 | 4 | 6 | 3 |
Calculate Spearman's rank correlation coefficient for these data, ranking depth such that 1 is the deepest reef.
Test the biologist's claim at a 5% level of significance. State your hypotheses clearly. (The critical value for n=8n=8n=8 at the 5% level of significance is 0.6429).
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.