International A Level Biology / Ecology

Spearman's rank correlation coefficient revision notes

Edexcel International A Level Biology (YBI11), chapter 15: Ecology, specification point A.1.9, A.1.7. Part of the full course.

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Spearman’s rank correlation coefficient uses the ranks of paired measurements to show how strongly two variables change together. Calculate it, compare its size with a critical value, then state whether the correlation is significant without claiming cause.

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• Core practical 11: random sampling with quadrats
• Core practical 11: transects and abiotic measurements
• Null hypotheses and choosing a statistical test
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