An environmental scientist wants to investigate the relationship between the density of the tree canopy and the biodiversity of the forest floor in ancient woodlands. They randomly select 10 different woodland sites of similar elevation and soil type. At each site, they record two measurements:
The following results were obtained:
Table 1: Canopy cover and understory species richness across ten woodland sites
| Woodland Site | Canopy Cover (%) | Species Richness |
|---|---|---|
| A | 85 | 12 |
| B | 40 | 28 |
| C | 65 | 19 |
| D | 90 | 8 |
| E | 30 | 32 |
| F | 55 | 22 |
| G | 75 | 15 |
| H | 45 | 25 |
| I | 60 | 18 |
| J | 20 | 35 |
The scientist decides to analyse the data using a Spearman's rank correlation coefficient test.
Explain why this is a suitable choice of statistical test for this investigation.
121 exam-style questions on AQA A Level Psychology Inferential testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.