International A Level Biology / Ecology

Spearman's rank correlation coefficient

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.

More lessons in Ecology

• Population, community, habitat and ecosystem
• Succession: from colonisation to climax
• Abiotic factors and population size
• Biotic factors: predation, competition and disease
• How the niche explains distribution and abundance
• Core practical 11: random sampling with quadrats
• Core practical 11: transects and abiotic measurements
• Null hypotheses and choosing a statistical test
• Student's t-test
• The chi-squared test