A botanist is investigating the relationship between the moisture content of soil, MMM (measured as a percentage), and the final growth height of a specific seedling species, HHH (measured in cm). The data for 8 test plots are recorded in the table below.
| Plot | A | B | C | D | E | F | G | H |
|---|---|---|---|---|---|---|---|---|
| Moisture (MMM %) | 25 | 12 | 38 | 55 | 30 | 42 | 18 | 50 |
| Height (HHH cm) | 18.3 | 10.1 | 25.4 | 32.8 | 15.2 | 28.1 | 14.9 | 20.5 |
Calculate Spearman's rank correlation coefficient for these data.
Stating your hypotheses clearly, test at the 5% level of significance whether there is evidence of a positive correlation between soil moisture content and seedling growth height.
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.